Credit: Brian Smith/Draft Magazine; Jessica Silverstein/Getty Images Photo: Who's Hotter: Bones' David Boreanaz or Castle's Nathan Fillion?

Obviously, hottie FBI agent Seeley Booth (David Boreanaz) is the biggest reason we stomach the grossness of Bones every week, while celeb author Richard Castle (Nathan Fillion) is why we love Castle so much — but which of these hunky crime-fighters snags the "Slightly Hotter" award?

Let's see... adorbz, crooked grin? Check, check. Irresistible, just-out-bed hair? Check, check. Smoldering dark eyes? Check, check. Drool-worthy bod? Check, check. Yep, these two studs are neck and neck. But if you had to pick one to take home, who would it be? Easy, ladies — both is not an option.