Alec just pulled all the way off when Jace froze like that, licking his lips and shaking his head, voice a little hoarse. "You're good. Do what you want. You can move. You can touch me," he promised. He kissed at Jace's stomach, scraped his teeth against his hip and nipped there before going right back to what he was doing.

He took Jace in again, but shallow enough that when he nudged Jace to move, Alec could move with him, not gag and just let Jace fuck shallowly into his mouth, hand pressing flat to his hip to hold him still whenever Alec pressed to take him deeper, then letting him move again whenever he drew back off.