They want to spend more time with it

"Oh, come now, Sherou. There's no need to be shy." Luvia drifted over to him, her sizable breasts bobbing over the water. Shirou gulped and felt his cock throb madly at the sight of it. Hidden within the water, it came close to three inches. Close but not quite.

"W-well, it's, er..."

Luvia latched herself to his arm. Again, her breasts were very soft and very noticeable. His dick pulsated.

"Mmmm...!" Rin watched, face red and jealous. She obviously didn't have the same thiccness as Luvia but...

"Oi, Shirou. You really love collecting girls, don't you?"

Plop! Just like that, Rin sat between his legs, her head tucked under his chin. Her glorious ass, although covered in water, rubbed against his tiny cock. Shirou could sense Rin smirking.

The glorious Tohsaka ass. Defenseless and now grinding against him.

Fuck.

Memories of it shaking. Memories of it walking in front of him.

And now it was naked and up against him.

"It's not like that." Shirou blushed. His cock throbbed again. Rin's bubble butt wasn't massive but it was shapely and well...perfect. God, Shirou had seen that ass of hers many times and it always worked well whether it was in a skirt, pants, or plain naked. With Luvia's tits on his left arm and Rin rubbing his cock, Shirou felt like he was in a dream. The warm water gave the atmosphere a subtle steam.