To Aru Majutsu no Index 15
I don't have particularly strong memories of the fourth novel; I enjoyed it, but it definitely was one of the lesser ones. The body swapping bit was also a fairly generic bit of comedy plotting.
It works ten times better in the anime.
Right about this point I was realizing that his cousin (as played by Misaka) is absolutely going to give any number of moefanatics a stroke, and those that survive will undoubtedly be undone by Touma's mom (as played by Index) and her teeeeeeny tiny bikini. The sheer calculated malice behind this due of nuclear punches to the more pedophilic segments of his audience definitely gives them an extra layer of hilarity, and he's not done there.
Each transformation manages to be absolutely appalling, the characters mapped to produce uncanny chills.
And the anime even put in a little topic joke of their own.
This absolutely destroyed me, and damn near destroyed my laptop, since I had just taken a big gulp of rum and coke. I'm glad J.C.Staff are aware that this is inauguration week, and decided to give the President props by turning him into a lesbian schoolgirl.