Biter is well spoken and intelligent, and is willing to do the menial tasks that Rachel demands. However he missed civilization while working for Bitch. Together with Barker, he claims to be fearless.
Biter gives off a brutish vibe. He is a muscular man over six feet tall, usually shirtless with a bear-trap jaw plate over his severe underbite and spike-studded gear such as a collar and a number of leather straps and belts. His teeth are filed into points. His costume combined casual wear with the already mentioned elements, fitting in with temperature and similar.
When operating as a cape Biter uses the before mentioned rusty bear-trap jaw plate and spiked knuckle-dusters. Sometimes he will rusty, old fashioned looking mechanical rigging The frame seemed set up to hold metal claws around his fingertips while allowing his hands the full range of motion. He would later upgrade the jaw-plate with a cleaner more stylized version, along with more spikes.
Biter is Barker's partner, they showed up in Brockton Bay to fight the Endbringer that appeared there. They were hired by Coil to work underneath Bitch. They have worked with her since she grabbed territory, but were not used during the fights with the Slaughterhouse Nine.
Biter would help against the Dragon Suits that were deployed against The Undersiders. The nascent Sons of Bitch would effect a strategic retreat from the conflict. Barker would later adapt to Bitch's leadership.
Biter and Barker would move to Earth Gimel with the rest of of the Sons of Bitch. Barker would later leave however and Biter would stay in Gimel with Bitch who he started a casual relationship with. The Sons of Bitch would stay in Gimel, sans Endbringer conflicts, for over two years before the Golden Morning came.
↑Biter – A tall, muscular cape with a homemade costume sporting a bear-trap jaw plate and spike-studded pads. Can distort parts of his body to increase their size. - Cast Page
↑ 2.02.1Biter Distorts the size of individual body parts Undersiders/Bitch Changer - Parahuman List, bolded edit by Wildbow
↑Someone who could alter their appearance to look like another person/alter their human features vs. someone who could physically take on another form. Biter would have likely been a shifter vs. a changer. - Wildbow on Reddit
↑Biter – Bitch’s underling, has powers. A brute with a bear-trap jaw plate as part of his mask and spiked gear, he can alter the size of individual body parts. - Cast (in depth)
↑Biter used the metal ‘bear trap’ jaw-guard in combination with his ability to distort parts of his body to large sizes, clamping down on the suit’s hand. He had to hurl himself back and out of the way to avoid the suit’s retaliatory attack. As he climbed to his feet, he spat out two fingers and a section of the suit’s hand. - Excerpt from Monarch 16.4
↑Biter leaped onto the machine’s back, his hands with the spiked knuckles worked into the gloves growing larger so he could tear the armor plates away. - Excerpt from Monarch 16.4
↑“Can’t,” Biter said. “Limit to how big I can grow myself before I do permanent damage.”
“Define permanent damage.”
“Stretch marks, scarring, permanent aches and pains. I have some in my midsection, all day, every day, it hurts.” - Excerpt from Monarch 16.4
↑ The Armband spoke. Losses are as follows: Debaser, Ascendant, Gallant, Zigzag, Prince of Blades, Vitiator, Humble, Halo, Whirlygig, Night, Crusader, Uglymug, Victor, Furrow, Barker, Elegance, Quark, Pelter, Snowflake, Ballistic, Mama Bear, Mister Eminent, Flashbang, Biter…--Excerpt from Extermination 8.3
↑The suit hauled the dog off it, climbing to its feet in an instant. It leaped forward to close the distance to its human opponents, and Biter stepped forward to meet it, his fist swelling to five times the normal size, along with the spikes and blades he’d worked into the fabric of his glove. The suit went flying, gathering itself into a rough ball shape as it careened backwards into the side of a train. - Excerpt from Monarch 16.4