Even though Harry'd been the one to say he wasn't going to last long, it was Oliver who felt himself (and his control) slipping by degrees. Every sound Harry made and the growing smile on Harry's face worked in tandem with the feel of finally filling Harry, of being with him completely. His eyes closed just as the final hold on his control gave way and he arched hard inside Harry, spilling into him with a groan of pure pleasure.
Slowly, and after many soft kisses to Harry's face and neck, Oliver's body stopped shuddering. He slipped from him reluctantly, using his wand to clean them both before dropping onto the mattress beside him. Body and mind still buzzing, he reached out and pulled Harry towards him, wrapping his arms around Harry's waist and dropping a single kiss to his shoulder.