There is this type of outfit called HxH (I don't remember the real name they use). It allows these girls (and guys I guess) to "make" armor for battle. The armor can fly and shoot and all kinds of shit like that. However, it only has a limited amount of power.
High school boy is recruited to attend a new school on an island. Actually, his sister works for the school, so she recruits him. Flash back to his childhood where mom tells him that because he can't make armor from his HxH outfit, he is worthless and must be left behind.
Fastforward back to modern day and he gets off of the train in this new island school research center. He meets a hot chick and the island is suddenly attacked by aliens. Her HxH armor suit has like 5% power left, which is enough for her to take out the first alien, but when a bunch more appears, her suit shuts down. High school kid saves her from falling, and his sister suddenly is speaking to him through a com unit. She tells him to fondle the chick's breasts. Then explore her entire body, before suddenly squeezing the tits really hard. Somehow, this miraculously recharges her battle suit up to like 90% power, which she uses to effortlessly wipe out the alien army. He doesn't know what happened, she doesn't know what happened, but somehow he has this ability to recharge suits.
The end.