Happy End no Kyuuseishu

Nao is a college student who draws indie eromanga. The morning after a grueling deadline crunch, he finds a little snakey boi, which invites itself inside his room. During a nap, it starts sucking on Nao’s willy and gulping down the seed… and of course Yasu, Nao’s kouhai, walks in. Dismayed as he is