Grooming is bad. And, yeah, I know, this probably won't be considered grooming, since it's a male student actively pursuing a female teacher, and that teacher is an otaku (which is fresh compared to all the tropes with mail otakus), but still. She is not resisting him that much even in the 1st episode, and him looking like her favorite character is not enough of an excuse.
Aside from that, I guess this is just not my type of humor. It is ok, flashy, expressive, sometimes over-the-top and sometimes kind of breaking 4th wall. Some people will definitely enjoy, especially guys, who had a crush on their teacher, and probably some otaku girls, too.