Ikaruga Iruma

The main protagonist of Dolly Kill Kill. Kinda cute isn't he heh?

Before the Dolly apocalypse, he was a high school first year and best friends with Matsun. He was on the baseball team and had a crush on the manager, Kumano Ren. He and Matsun were known as the Freshmen Duo.

History
After winning a baseball game, Iruma and his team decide to go for a swim in the pool to celebrate. However, their fun is quickly cut short when a swarm of bizarre Wasps begin to attack and kill most of his teammates. Horrified, Iruma jumps into the pool alongside his two best friends, Matsun and Kumano, so as to escape the Wasps. After a while, the trio resurface to find most of their friends either dead and dying.

Not having a clue what is going on, Iruma's group decides to hide within the school where they observe the chaos going on outside. Then, without so much as a warning, a strange doll-like creature crashes a jet into the school; resulting in Matsun losing a foot.

Desperate to save his friend, Iruma carries him and runs with Kumano to safety. However, another doll monster appears and tries to suck them all in using some kind of vacuum-like device. Matsun, knowing he won't make it, decides to sacrifice himself in order for both Kumano and Iruma to escape.

Consumed with fear and grief, Iruma and Kumano run frantically until they reach a bridge in which a giant pole comes down and cuts it in half, separating the pair.

Kumano falls into despair upon seeing that she and Iruma can't get to each other whilst Iruma can only look on in horror as more dolls begin to approach Kumano.

Believing that everything he cares for is going to be taken from him, Iruma then says: "It's end of the line", before immediately blacking out and then awakening in front of his house, which is now on fire.

An unspecified amount of time has passed and we find that not only has Iruma become suicidal, but he's also gone mad with despair, having taken a pair of store mannequins, dressing them up like Matsun and Kumano, and taking to them like their still alive.

While scavenging for food, Iruma sees a girl being harassed by a pair of thugs and mistakes her for Kumano. He tries to defend her, only to stop when he realizes that Kumano is dead, enraging the men who threaten Iruma with a gun.

However, the girl (who's named Banira) then suddenly proceeds to beats up both guys and saves Iruma.

Outside, Banira also saves Iruma from a sudden Dolly that appeared. She then recruits him to join Trial and Error and drags him to their HQ, introducing Sakamaki and Daifuku to him along the way. Iruma sees the Wild Dolly again during Trial and Error's attempts to capture a Pregnant Dolly, and goes berserk--wanting to avenge Matsun. He and the Dolly fight, surprising everyone when Iruma is able to pass through the Dolly's barrier and attack it. Iruma then gets captured by the Dolly, who tries to take flight. But Banira shoots down the Dolly and lures it to a trap that Daifuku activates.

Iruma and the Dolly fall into thermogelling polymer, which traps the Dolly. Iruma still wants revenge, but the Dolly manages to break free. He is rescued, but has lost a foot and is taken to the hospital.

After a stint in the hospital, Iruma attempts to set out to the Dollhouse after hearing that it is where captured humans are kept. As they discuss the Scepter of God plan, Iruma becomes more desperate to get to the Dollhouse. He tries to get there on bike, while Banira finds him and scolds him, but then relents and drives the bike in order to get him there. However, the Scepter is dropped before they can get there, and Iruma gives up in despair. Daifuku arrives and reprimands him, but also relents and uses the helicopter in order to get them to the location of the Dollhouse.

Upon arriving at the Dollhouse, it is found out that things in contact with Iruma can pass through barriers. They arrive and see Kyujin and Bugs, a rare Plushie type Dolly, fighting. Iruma demands to know if Kumano is alive, which Kyujin responds that she ran off into the forest that used to be there. However, Iruma aggravates Kyujin and he ends up saying that she's dead, and blaming him for leaving her before. Iruma then snaps and goes berserk, jumping towards Bugs. However, Bugs snaps his arm off and throws him around, throwing him into the helicopter and destroying the helicopter and the remaining people inside, much to Banira and Daifuku's dismay.

Bugs grabs Iruma, who is shown to still be alive. Iruma suddenly regenerates his missing foot and arm and shows super strength and speed, managing to destroy many approaching Pygmy Dollies and be on equal ground with Bugs. Kyujin, not one to be one-upped, joins in on the fight. However, Iruma's body is not used to his new powers, and his regeneration is causing him to also grow weaker as it pulls tissue from other parts of his body. He passes out, with Kyujin comedically exclaiming about how he wasn't that angry and shocked that he passed out--assuming it was from his anger. Sakamaki arrives with a helicopter and Daifuku throws Iruma at him, in order to let the helicopter pass the barrier. They escape, but Kyujin is left behind when Bugs grabs onto him.

He is then in a coma after the fight, but awakens when Kumano is mentioned. Kumano tells him she is training in order to fight on equal ground with him through Kyujin's blog, and it invigorates him. He begins training with Sakamaki in order to grow stronger. He also seems to have matured and is not as emotional and irrational anymore.

Abilities
So far, Iruma has demonstrated himself to have impressively high stamina, even when injured.

In the beginning, Iruma primarily used random weapons (such as a pipe, a katana, and a gun) against Dollies which, despite other people using similar tools to no avail, managed to break through their barriers, indicating that he possesses hidden abilities.

He is also shown to be a good marksmen in chapters 48-50 when he targeting a Dolly's barrier eye.

During the fight with Bugs alongside Kyujin, Iruma awakens his innate abilities which not only increase his physical capabilities to superhuman levels, but also grant him a powerful regenerative healing factor; these powers becoming even greater when he goes berserk.

However, there seems to be limits on Iruma awakening as shown when he passed out during his fight with Bugs, but its unclear whether or not its because of him putting too much strain on his body (though in chapter 42, Iruma was shown to be noticeably thinner).

He gained his abilities when he consumed the Wasp's venom, which can be seen in chapter 1.