1. for 田部, sent wine like we did in the demo. Then I go for 大道寺 the young muscular guy scenes by sending her around 5 meat. And I (not sure if its a must...
edit:seems unnecessary) lower her faithfulness to like 100 (you probably need to raise her lust/frustration in order to do that quickly). after a few scenes with 大道寺, 田部 will install a detectaphone in the house (or sth like that) and use her affair with 大道寺 to blackmail her. but i cant reach the end since theres a fatal error (fixed
here).. i'm not sure what will happen if you go for 龜's route after you started 田部 route.
2. for 龜, send her around 5 photos of roses, lower faithfulness
(edit:seems unnecessary.. actually u do get extra scenes when faithfulness is below 50) but try not to reach 0 unless there are no more scenes. when there are no new scenes, you can drop faithfulness to 0 and get the ending (the ending is same if you reach 365days).
3. for 大道寺, i haven't finished his route yet, but its triggered by sending her around 5 meat. edit: finished, very straight forward and this guy has lots of scenes.
(edit: drop ur faithfulness to below 50 for extra scenes)
I think i have completed the main route of those 3 guys but I'm still missing 5 scenes, maybe those are for happy ends. but judging from the gallery allocation, it seems there are still some scenes related to 龜 or 大道寺.. edit: seems like theres and ending when she has sex with different people and gets pregnant