“I love kissing my boyfriend,” says Krysten Ritter, actress and star of the sitcom Don’t Trust the B---- in Apartment 23. “It connects you.” Kissing is what bonds people together — or if you’re a bad kisser, it’s what makes people run in the other direction. “During a lip-lock, the brain releases dopamine, which is responsible for feelings of desire and bonding,” says Dr. Yael Varnado, founder of Get Checked 4 Life, a nonprofit organization that provides access to health services for at-risk communities.