Our emo boy!

Here's Daigo!

As a Demon Slayer, his Breathing Style would be Wind Breathing, and he would know all nine forms (also two swords because Doomscizor has two scythes).

As a demon, his Blood Demon Art would be Total Black. He can manipulate the shadows within his cloak to create several tangible limbs for combat - mostly arms. He can also release the shadows like a cloud; if his opponent gets trapped in that cloud, he can smother all of their senses - sight, hearing, touch, smell, taste - to the point that they're completely numb. In that state, they're totally at his mercy.

What do you think?

And Shu's next on my list!