Wally always had image issues growing up. Becoming Flash's bitch helped a lot. He got to feel good about himself, saving peeps from baddies and all that. It gave him confidence. Allowed him to grow as a person and become happy with himself. However, his positive body image shifted when he met Robin. Manly Robin, muscly Robin, acrobatic Robin, well endowed Robin. He was a hunk and Wally was a scrawny little cunt fuck. Robin could do everything, that's what happens when you're trained by The Batman. All Wally could do was run kinda quick.
He fastly distinguished himself as the comic relief character-copying his golden one-liners from The Flash. When he was a kid, before he went under the wing (or rather, bicep) of The Flash, he had found "Flash's Guide To Joking" in an old library discard box. All The Flash's golden one-liners were stored within the pages of that wonderful paper back joke collection of a book. He studied it like everyday was the day before his history exam and he hadn't studied at all the previous week.Anyway, back to Wally's image issues, he was very jelly of Robin's sculpted physique. He would watch him during training hours, when his dark mop of hair hung limp with sweat across his forehead and his well toned muscles rippled across his arms and chest and legs and shoulders. Wally especially enjoyed watching Robin in hand-to-hand training, when his agility and skills truly were on full display. He had a brain to match his brawn, and Wally admired it. Even with Wally's supah dupah speed, he could barely keep up with Robin's attacks. So it wasn't surprising that Wally would often spend 10 minutes in front of his mirror every night to critique his body, and spend hours at night lying in the dark pondering his short-comings in life.