>Mahiro's attitude towards Nyaruko was, in fact, totally justified
>So... the Ancient Evil won?
She is an Eldritch Abomination. Not you're waifu.
It was probably an orgasm that included things astroprojection, glimpses of alternate realities, and subversion of space-time to appear to your past self and trying futility to warn you past self of the coming danger.
You can't say you love you're waifu if you're not prepared to be tentacle-raped by her.