It doesn't feel like anybody's getting it:-
Ayaka's mother-in-law is forcing Tougou into darkness, into her world, having warped, Wicked personality, he tried to save Tougou and his mother from all that (through warped ways, as he was also always that wierd)
But consider this:- he was bought up in a Good Enough Environment, but always felt out-of-place, he concluded he was different from all those he lived with, he felt alienated. That's why he wanted to see her mother.... But wanted to Bring her to light, towards real happiness and not just the wierd kind she got over her son-complex from Tougou. That's why he took drastic Measures that make no sense (cuz, Don't forget, he's got a Wicked personality too)