Energy Suck

An Emitter Quirk that normally demands contact, Energy Suck belongs to Rikiya Katsukame. It arrives in Chapter 156 and in Episode 76 of the anime. Under the influence of the Trigger drug its range widens from touch to close range.

Physical contact plus an inhale is all it takes. Vitality drawn out of a target flows into the user, who gains stamina and swells in both size and strength. The trade runs both ways, so every gain Rikiya makes is a loss inflicted on whoever he has hold of.

Deny him contact and the Quirk does nothing at all. Trigger erases that limit. With the drug amplifying him, breathing alone pulls vitality out of everyone nearby. When the drug first took hold he was unconscious, and the Quirk fired entirely on its own, drinking in enough to wake him and refill his reserves.

Rikiya Katsukame is the only known user. Ryukyu, who ranks tenth among Pro Heroes, subdued him quickly before he dosed himself. Afterward he held even for twenty minutes against her, Nejire Hado of U.A. High School's Big Three, several more Pro Heroes, police, and interns, and only fell to a combined attack once the drug wore off and the weakened heroes of Ryukyu's office could regroup.

The concept borrows visibly from the Superman antagonist Parasite, who likewise siphoned strength and energy through touch to temporarily add it to his own, and who at points managed the same without physical contact.