For stand up at night you need >50% lust, i know you can escalate this with sniffing or licking sister's pants in bathroom, maybe game have some more things for lust but i don't know now, and sorry for my poor English, oh I read right now you can go sleep before 20:00 I hope it can help you
Sister's smile is equipment, if i remember this up your stats, you can equipped smile in abyss, or I badly understand your questions?
