When does a game stop being casual and become hardcore? Frontier of Sister Indulgence ~Tale of Lust in Poluluka~ toes the line between the two, exploring dark themes in a picturesque world.

Frontier of Sister Indulgence ~Tale of Lust in Poluluka~ is a village life simulator developed by fushidaratei. The game is a spin-off to fushidaratei’s Delta series, taking place in the same world and even features recurring characters, but centers on a story unrelated to the franchise's main entries.

The game takes place in the titular Poluluka Village, located on an island of the same name. The protagonist of the game is a young, effeminate boy named Phai, who is rescued from the slave market of a neighboring city by a young woman named Rodeaux. Soon after, he's accepted into Rodeaux's home in Poluluka, which also houses her two sisters, Alya and Mana.

Frontier of Sister Indulgence is a slice-of-life story divided into four chapters. The first three are dedicated to each of the three sisters, while the final chapter allows the player to freely enjoy their time with everyone. Throughout the story, Phai will be doing his best to support the sisters in any way he can, and involuntarily ends up cuckolding other young men in the noticeably small village.

There are only thirteen characters living in Poluluka Village, excluding Phai, and most of them have barely any importance to the story, with the main stars of the story being the sisters Phai gets to live with. Rodeaux, the oldest of the trio, is a genius (if overly excitable) inventor. The second-oldest, Alya, is a trustworthy, but lazy tomboy, easily prone to bouts of envy. Finally, Mana is the youngest of the trio and arguably the most hardworking, but also the most naive. Each sister has a personality distinct enough to make their own dedicated chapters uniquely their own, while simultaneously maintaining chemistry that allows for fun and dynamic interactions with other members of the family and even the villagers in general.

The villagers include the likes of the old village mayor, the kindhearted owner of the local pub, the delusional shopkeeper and his prideful sister, a stubborn researcher analyzing local marine fauna, and the sister’s three childhood friends. While Rodeaux and her closest friend may have no feelings for one another, Alya has an incredibly awkward admirer, and Mana keeps getting bullied by the only boy her age, who feels entitled to her attention.

For the most part, the player will interact with other characters during event cutscenes, of which there's an abundance; however, aside from the two boys who rival Phai for the sister’s attention, as well as Alya’s female friend, all other characters have only a passing presence in the story. Not only do they fail to leave any real impact, but they also fail in helping make the village feel more alive.

Aside from cutscenes, the player can interact with any of the villagers by approaching them during the day, but even then, they serve mainly as window dressing. Each character has a sentence or two to say (usually involving fishing advice) depending on where they stand at the moment. The game features a daytime system, but there's no calendar to go along with it, meaning every day is Monday, and everybody is doing the same things and saying the same lines. The only difference is when it rains, as then most characters aren’t available at all. Sadly, while each chapter unlocks new events, the villagers stay the same, no matter how far you advance into the game.

Thankfully, while Frontier of Sister Indulgence may not utilize its cast to its full potential, it still has a worthwhile story. The slice-of-life narrative manages to stay upbeat through most of its run, with occasionally tense, if predictable, twists. The sisters stay consistent in their behavior, and the hijinks they get into can be quite comedic, if not just for their grounded absurdity.

It should be noted that Frontier of Sister Indulgence isn't a game suited to everybody’s tastes. Given the game’s description and idyllic tone, it’s easy to expect a more vanilla experience; however, the story introduces some darker tones right from the get-go, including the likes of slavery, objectification of humans, and even allusions to eugenics. These themes aren’t exclusive to the background of the story, as the girls themselves can behave in reprehensible manners, often pushing Phai past what he finds pleasurable, if not just raping him for their own various reasons.

Despite many of the game's darker themes not being advertised by tags on the store page, I didn't have any major issues with them, and so I was able to enjoy both its elements of lighthearted comedy and occasional dark twists. One particular area worthy of praise in Frontier of Sister Indulgence would be its more organic dialogue, which comes off naturally even during the sex scenes, a feat that can be challenging for many writers. In this case, the game gives a robust background to each encounter, letting characters have a legitimate conversation during intercourse. All dialogue in the game is spoken, while basic pixel art animations portray events in place of narration.

There’s much less to be said about the gameplay portion of Frontier of Sister Indulgence, though. You can walk around the small village looking for new events or jobs to take for the villagers. Both the available events and jobs are always marked on your map, meaning there’s no real reason to explore. Instead, you will find yourself in a loop of checking your map, going to the next stop, initiating an event, then opening the map up again, as if the village itself is just an elaborate menu screen. The events and most of the jobs play out as mere cutscenes, with no gameplay attached to them.

The sparse, more elaborate interactions involve fishing, farming, and two minigames done with Rodeaux, with both fishing and Rodeaux’s jobs playing out as quick-time events. They’re fine, but they're not exactly big selling points. The type of fish you can catch depends on which bait you use, where you fish, and what time of day it is. You do have to get each fish at least once to reach the ending, but you can skip that by buying an appropriate item through one of the NPCs.

Farming, though, is a bit more interesting. You have a field of nine squares that you can fill with seeds of various plants. All vegetables will grow up in three days, but depending on what you planted and how you arranged the vegetables, their value will increase by a percentage. There are eighteen patterns to unlock, but because there are no seasons or any major changes to the game's daily routine, there’s no reason to plant anything other than your most valuable pattern. This means that the minigame becomes mindless right away. The limited plot size isn’t a bad idea, as with a limited space to manage, you end up having more time for other activities. Ultimately, though, farming overall just isn’t deep enough to stand out as a meaningful feature.

Visuals in Frontier of Sister Indulgence are mostly composed of pixel art with sprite-based cutscenes. Occasionally, dialogue may use illustrated character busts instead, but it’s more uncommon. The actual quality of the pixel art is serviceable; while the actual designs are distinct, the characters themselves look muddy, even when playing in a window at the game’s preferred resolution. Erotic scenes are well-animated, though their real strength is in their variety, with the game containing thirty different scenes. When it comes to the game’s music and sound effects, there's nothing of real note. While there's a couple of songs in the game, the only memorable one is the village theme, perhaps due to being played the most often. There's not much to discuss on the more technical side of things, as I didn't experience any bugs during the twelve hours it took me to beat the game.

If I were to sum up Frontier of Sister Indulgence ~Tale of Lust in Poluluka~, it’s a great visual novel, but a bad life simulator. Its attempts at simulation elements are meant to add some charm and build a sense of belonging between the player and the village, but not enough effort was put into the gameplay to accomplish that. Thankfully, the story can be enjoyed despite that, and it's a really solid, but slightly predictable slice-of-life comedy set in a surprisingly dark world. I don’t regret my time with the game, but I would love to play a better, more realized version of it. As it currently stands, I recommend at least waiting for a sale.

You can buy Frontier of Sister Indulgence ~Tale of Lust in Poluluka~ on DLsite for $21.01 (estimated from ¥2,200). A demo of the game is available on the store page.

In order to play the game properly, you will have to change your system locale to Japanese. DLsite offers a guide on how to do so here. If you skip this step, no text will appear in the game.