Sore wa Yappari Koi no Sei!?

1-4) Sore wa Yappari Koi no Sei
One day, the unlucky Taira dives face-first between the legs of the judo club captain, Kusehara! Kusehara then insists that Taira 'take responsibility' and starts to enact various perverted things to him every day!

5-6) Sore mo Yappari Ai no Tame
Ibuki and Kazoumi are childhood friends and they live together since Kazoumi's parents left the country to take care of overseas business arrangements and because Kazoumi's father and Ibuki's father are friends. Since then Kazoumi takes care of Ibuki, who is the spoiled-unaware type, but he wants more...

(from M-U)