The Unknown Man, also known as The Hunter and Sunglasses, is a minor antagonist of the Elfen Lied manga. Despite having a short appearance, he is constantly referred to as the most despicable villain in Elfen Lied due to his sickening actions.
Absolutely nothing is known about the Unknown Man, including his past and even name, as the Unknown Man is simply a fan-made moniker. He first appears in Director Kakuzawa's grotto where he and Doctor Arakawa are tasked with finding and capturing the Diclonius Lucy. The Unknown Man then makes a wager with Arakawa; whoever finds Lucy first can make her their sex slave. When the races begin, the Unknown Man finds another Diclonius imprisoned at the facility named Number 28, where he proceeds to rape her violently before putting a device in her that makes her a living Diclonius-tracker and puts her in excruciating pain so she can't use her vectors. He then amputates her lower half before stuffing her in a satchel, slinging the sack over his back like a book-bag, and starting his hunt for Lucy.
28's, just a few hours away from death, Diclonius-tracking device leads the Unknown Man to a house containing Nana, a Diclonius, Mayu, a sweet homeless girl, and the latter's dog Wanta. Enraged that 28 led him to the wrong Diclonius, he slams the sack containing her on the ground, killing her instantly and putting her out of her misery. He then paralyzes Nana by firing a crossbow shot spike-ball in her stomach and attempts to rape Mayu after kicking Wanta out of the way. However, before Mayu is raped, Bando arrives and shoves a spike-ball up the Unknown Man's rectum, making his waddle away in fear.
Healing his wounds behind a boulder at the beach, the Unknown Man is surprised to see Bando and Lucy arrive, completely oblivious to a spectating Unknown Man. The two then begin to have a showdown, until the Unknown Man jumps in the way and protects Lucy, begging Bando not to kill her as she is too important to the Kakuzawas' plan. Lucy then rips the Unknown Man's head off with one of her vectors before brutally chucking the severed head and Bando.