From Shinmakoku Scanlations :

One time during his high school years, Hosho impulsively dry-humped Saotome, his soccer club senpai whom he admired. After the incident, they didn’t speak of it again and their relationship became strained. It’s been eight years since… Hosho is now a #1 host and has recently moved. However, the landlord living in the apartment next to his is none other than Saotome! Hosho is engulfed in complicated memories, but he is wary of Saotome’s unchanging kindness and the reasons behind his own impulsiveness eight years ago! This is the heart-jerkingly pure love story of Saotome, the too-cute-to-be-true landlord and Hosho, the host whose talents are wasted on him.

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 Attractive Fascinante:

The infirmary sensei, Odagiri, always said that students were out of his strike zone. One of the students, Izumi, kept coming back to seek a physical relationship with him. He heard that Izumi was a player, but he soon realised that it was Izumi’s first time when they started to feel each other up. Odagiri stopped at that very moment and told Izumi never to look for him again. However, Odagiri got upset when he saw Izumi flirting with another student. Was it love?