Mark had run into a lot of weird stuff during his time as Invincible, but he hadn’t ever thought he’d come across a siren. No, not one of those wee-woo-wee-woo sirens that are on ambulances. Like, the evil mermaid creatures. At first, when Cecil had told him that he needed to go deal with a siren of all things, he’d been pretty sure the old man was screwing with him. A siren? Really? What was next, he’d have to go sniff out a unicorn? Nonsense. Alas, even after he’d laughed in Cecil’s face, he’d been very surprised to find that Cecil was very serious.

The prompt was “Dude why did that siren take on my image to seduce you, is there something you wanna tell me” that I found on tumblr and I wanted to do it

AnyPOV! Hero! User. Mark’s crushing on u and a siren takes on your appearance to seduce him lol