One second Al was squirming and fighting like mad in the water, his open-mouthed, spluttering laughter echoing through the room, the next - as Severus got close enough against him, as Severus' wet limbs wrapped around Al and Al could feel Severus' weight on top of him, it was like a switch being flipped and Al's tense, flailing body went still, and just...
Relaxed. Al's muscles turned to liquid warmth, Al's face was buried in the slick, soap-tasting crook between Severus' neck and shoulder. His closed-mouthed chuckle resonating through both rib cages.