You know what's even funnier? Zenkichi tries to make an excuse that he needs to go somewhere after this. What does she do? She stabs him in the foot, so that he can stay by her side. FOREVER.
Also, need I remind everyone that Medaka Box is also authored by Nishio Isin, the same guy that brought us Bakemonogatari and Katanagatari. Heck I'm surprised that we didn't get such a long-winded character sooner.