Tsukune on the girls.
Moka:
Moka-san's fabric feels good.
Kurumu:
Kurumu-chan's lace
Mizore:
and Mizore-chan's stripes
Kokoa and Yukari:
Yukari-chan and Kokoa-chan's folds are perfect too
Ruby:
.........
Ruby - Ignored!!? You Ignored my bathing suit Tsukune-san!!?
Kokoa - He just didn't want to say G-String.