I feel like Scott would be one of those boys that just always comes pre-maturely. Especially after their little adventure and with how he had to hold off until they were home. He’d probably only rub the fat head of his dick against her labia to shoot of; get a creamy mess between Allison’s thighs which she’d have to content herself with; get herself off with desperate fingers on her little plump clit, the way made smooth by Scott’s cum.
Scott also would never be ashamed about how quickly he shoots tbh. Just have this earnest, happy smile on his flushed face.