The Amazing Spider-Man #226

Synopsis

Felicia Hardy, the cat burglar known as the Black Cat, has faked insanity in order to be placed in a mental institution, which proves easier to escape from than prison. On the prowl again, she starts stealing from the mob. When Spider-Man tracks her down, the Black Cat says that she wants to help him fight crime, and after proving this with her actions, the new crime fighting partners unite in a kiss.