Taking care of my pet
For me the hardest part of the game by far is taking care of Karin.
My favourite leveling up-moment is definitely the pet becoming a maid :)

I'm always so focused on getting good stats and dating the girls I just completely forget about her until one day I think: "Oh my god, I totally forgot about the semi-nude girl in my basement!".
That's a sentence I never thought I'd say :p

What's your personal struggle when playing this game?