Dagger (Marvel) Wiki

Tandy Bowen, known alongside her partner as "Cloak & Dagger", is a superhero appearing in Marvel comic books. They debuted as a duo in Peter Parker, the Spectacular Spider-Man #64, published in 1982.

A teenage girl with rich parents, she was neglected by her mother, and a breakup with an older college student left her despondent, causing her to run away from home.

She meets Tyrone after he prevents a thief from stealing her purse. They quickly become friends. Shortly thereafter, they're abducted by the Maggia and used as guinea pigs for designer drugs. Tandy, Tyrone, and a Chinese immigrant (later retconned to be Mr. Negative) were the sole survivors. The pair eventually escapes and discovers that the drugs have granted them powers.

Cloak can teleport and turn intangible through the darkforce. Dagger can create daggers and heal through the lightforce. They draw power from one another, further strengthening their newfound bond.

They are closely associated with one another, but given the nature of image boards, you are more likely to see artwork of Dagger without Cloak than Cloak without Dagger.