If you're looking for manga similar to Zulllu: Pluggin' Away, you might like these titles.
Meet Kurumada Rinta, a man who has been well-endowed with a seal-shaped member who can think, speak, and has a thing for clams.
Includes the following chapters:
One day, she verbally abuses me all of a sudden... and it just doesn't stop there.
There’s not much Akari cares about in this world, except maybe her friendship with Fumika, who’s afraid of boys. But then Fumika gets a boyfriend, and something happens that makes Akari even more jaded than she already was.