e621 ball beach beach_ball beach_umbrella bikini breasts butt canine clothed clothing cloud dog feline female flip_flops fox group human inflatable kemonono looking_at_viewer looking_back male mammal outside pool_toy seaside side_boob skimpy sky swim_ring swimming_trunks swimsuit teenager water young
 

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I suppose that's his actual girlfriend or his childhood friend in the tube over there.