fukubiki triangle
tropical kiss
etc etc etc
those are actually good hentai lol
EDIT: since hentai was mentioned why don't I give a list?
Eroge!
Tropical Kiss
Oppai Gakuen Marching Band Bu
Honoo no Haramase Paidol My Star Gakuen Z
Honoo no Haramase Tenkousei
Nuki Doki
Boy Meets Harem
Shocking Pink
Kagaku na YatsuraAneimo
Baku Ane Otouto
Resort Boin
HHH Triple Ecchi
It's A Family Affair
Fault!!
i've seen all of 'em and i can say they were good.