That pleading just goes straight to his dick, and warms Len from the inside out in a thoroughly pleasant way. What he wouldn't give to hear the Flash begging him like that on a daily basis? He'd give quite a lot, anyway.

"Nnngh," he groans, hooking his arms under Barry's legs and forcing them up and out to give him total access as he begins to thrust. "That's it, kid," he purrs. "I've got you."