No, don't stop!
"Pull my skin up further," he suggested, wanting her to try again.
"But I don't want to hurt you," she complained.
"You won't. You're not pulling nearly hard enough to cause me discomfort," he reassured. Then, trying not to sound like he was begging, he said, "Please, try again. That felt amazing."
"Okay." She nodded.
Then she pulled up on his shaft, pulling more foreskin up around his glans, then tried again. She again slid her tongue down into his tube of foreskin and pressed it between skin and glans.
This time, when she slid her tongue around his glans, she made it all the way around. As her tongue circled around, the sensation of it gliding across his glans and under his foreskin sent tingles through him. And, as her tongue ran across his frenulum, jolts of intense pleasure rushed down his shaft and gather in his balls.
"Oh, god baby, that's amazing," he gasped. "More, keep doing that."