Well, I don't know the formula. I've played Incest games that try to tell a story and most fail. The premise is usually the same "Dad died. Moved in with Mom/Landlady and her daughter/s" However, while the premise to this VN is different and more unique than the cliche example i just used, it's not the reason this is so good.
Why? Is it cause most titles refuse to look at their game as anything more than Fap material and this game breaks that trend? Is it cause this MC has actual goals to complete? Is it because the dialogue (not bad, but sometimes has different gender pronouns) feels like these are actual people? It's up in the air a this point
But a more structured review.
Archetypes and MC: There are archetypes here for sure. The shy/insecure girl, the slutty one, the family member that is secretly in love with MC, the punk kid, the overworked dad. However, even in these roles, they are delved into. The main character I like, he is a bastion of good not because he's trying to get into anyone's pants, but because he generally is and is interacting with (Not really a spoiler since it's in the intro, but just in case)
his children so it's a lot more natural. He's trying to help them and is understanding them even as learns to accept his new role.
Pacing: I feel the pacing is pretty good maybe a little fast with
his new sister but I hope to see the dev make the relationship take flight in a natural and satisfying way. To be fair, they were drunk. There are only 2 chapters as of now, but each one tackles a 1 or 2 day arc of sorts. Each one resolves in a satisfying way and it feels like the MC is getting closer to fulfilling his obligations and getting closer to the people that matter most to him. ALSO, he doesn't act like an immature brat trying to bang all his daughter.
However, he's not too bothered by making out with his sister and checking out his mother because he's never known that as that BUT even then, he's still very respectful and gentlemanly which is rare in an MC.
Graphics/Characters: I LOVE it. While Zoe looks average, I'm a big fan of Emma and Ruby. Ruby is the classic beautiful/hot girl, but she's really inexperienced and rather sweet. Her design informs you that she's a popular girl, but she just wants to spend to time with
her brother. Emma on the other hand is the "ugly" fat girl. I say that as her role, she's beautiful and cute and gives the MC a lot to work with. She has extra baggage which allows a LOT of character growth and development. The MC did a number on her in
both bodies in the past. He's now trying to fix his mistakes and giving her the support she needed all those years. Really good characterization so far. Lucas is okay. He's meant to be the snotty punk kid, but he's just young, lost and stupid. I hope that he is also fleshed out some more. Not a fan of other guys joining the main party (Unless your name is Liam) because of the circumstances and the well meaning nature of the MC, I'm rooting for him to put things right.
Anyway, TLDR, Pacing feels just right, I love the chubby girl and inexperienced popular girl and the MC is pretty cool too. He doesn't act like a little perverted kid all the time.
If you read this @Zargon_games I enjoyed your game A LOT. I like the slow pace you have going so keep it up!