Windows.

Keigo Takami, or Hawks, had a love/hate relationship with them. He could look out at the world through them on his rare days off while he does literally nothing except lay on the couch and scroll through media. However, he occasionally tended to fly into them, like the bird he might be. It happened more often that he'd like to admit.

...

As in, at least twice every four months.

Yeah, he had a lot of window incidents.

You'd been half asleep on your couch in your apartment, watching a so-bad-it's-funny American movie, Sharknado, blanket drawn up to your chin and eyes slowly drifting shut. You'd just about to pass out when a loud 'THUNK' oh-so-rudely interrupted your plan. You pushed off the couch, tired and annoyed, blanket wrapped around yourself as you flung open the sliding glass door, expecting a big-ass bird or something. Instead, you got...

... A rather famous, red-winged blonde laying unconscious on your porch, with a smudged mark on your glass door.