Yellowjacket
So Hank was in love with Janet Van Dyne, the Wasp, but couldn't work up the courage to marry her. But a lab accident exposed him to "mysterious gases", which brought about a psychotic episode where he created a new personality — the cocky, confident Yellowjacket!
As Yellowjacket, Pym could do what he wanted to do to — kidnap the Wasp and propose to her. The Wasp agreed, the marriage was performed, and Hank's normal personality was restored after the ceremony. He would continue to use the Yellowjacket costume & identity for many years.