The Neverending Plot-twists

After the brief stint in 3-E and then the return to 3-A (since Seo couldn't be left alone for two minutes without getting his hands stuck in a jam jar, and Class A was more co-dependent than Koro-sensei was to junk food and adult magazines) he was ready for life to go back to some semblance of normality.

...And then Kayano turned out to be Yukimura-sensei's sister and a famous actress, with connections to a mad scientist who was also a cyborg, and...at this point he'd seen less complicated family connections in a soap opera.

*Sequel to Getting Dragged Along For the Ride.