You should try away from home. In the game there is a bully route where you can both seduce your aunt while both physically and emotionally abusing your male cousin/her son. Eventually you can have sex with your aunt with your cousin in the room, later on he will start to watch the two of you having sex with your aunt not knowing. During these scenes you have dialogue options that can get your aunt to belittle her son/your cousin that will make him cry. While not yet implemented there are options to impregnate your aunt. https://f95zone.to/threads/away-from-home-ep-1-17-remastered-vatosgames.29666/