[Gasping at that bite on his thigh and shuddering with how he holds still and stays in place so he can't mess up anything Iwaizumi has started, Oikawa makes a soft keening sound in the back of his throat before he twists his wrists in place, panting.]

I'll warn you instead of saying yes, I want to put my arms around your shoulders and hold on, I'll want to feel your back and neck and hair. Is that containing myself, if I only touch you there? [He can't, he'd really try but he can't guarantee he wouldn't be able to keep his hands off him for long - so if keeping him tied up is what lets them be able to keep going, then he'll stay tied.]