For nostalgia sake. Plus it reminds me of my first kiss.
This one is interesting, it was on late at night in Japan. So the producer wanted an energetic song to open the show to wake people up. However once you watch the anime itself, the opening is far more interesting.
Tower of God is a far cry from a hype show with a dead weight protagonist and a useless antagonist, but that opening is the definition of fire!
I will happily die on this hill alone, hahaha!!!
"Kokkoku". It gets you really hyped up and I love the animation. On second place I would put "Devilman: Crybaby".