How old should my character be?

I'm writing an R-rated superhero story. My main character gets his powers from breaking into a lab and getting exposed to radioactive chemicals. His boyfriend, who's older than him (maybe 6 to 10 years older), is murdered, and he kills his killers. My main character is bisexual, and most of his love interests are 6 to 10 years older than him—maybe some even older. His best friends are in their 20s and slightly older than him too. He's a playboy, he drinks alcohol, engages in drug use, and his superhero lair is above a strip club. But I don't know how old he should be. I don't want him to be 25, so he would have to be 21 to 23. But I was thinking about having him be a teen hero, similar to Spider-Man, maybe 16 or 17.