Water Absorb: You yourself are water and water and water water and so you simply absorb the opponent's water-type attack as more water 
Vaporeon, normally:
water and water and water water
Vaporeon, after being hit by a water-type move:
water and water and water and water water
Follow
@vaporeon_ what if 
gets hit by a water-type move again?
@aescling Also, full HP :3
@aescling water and water and water and water and water water