Yes, very late for Summer, but here is it anyway. My very personal and selcted waifu harem enjoying a day out on the beach. ^^
Just in case you don't know some of them (I'm assuming you at least know Krystal or Shampoo... ¬¬), from left to right:
Mina Majikina (Samurai Spirits), Menat (SFV), Krystal (Starfox), Kurenai (Sengoku 3), Shampoo (Ranma 1/2) and Junko Enoshima (Dangan Ronpa)
I just love them too much! X3