Splendorman is the Slenderman's brother and, as opposed to his brother, loves everything happy and joyful. His purpose is to cheer up people who do good deeds. He is happy-go-lucky, and very kind, especially to children. He often brings people gifts such as flowers. He has a visible face that consists of black dots for eyes and a black mouth, but he lacks teeth and a nose. He also wears a black suit with colorful polka-dots, a red bow tie  and a top hat with a red stripe. He is also very tall.

The cheerful and kind brother of Slenderman

The Slender Man is a widely popular internet urban legend, horror icon, and very commonly the titular main antagonist of many stories involving him. Slender Man is a humanoid creature with a vast array of supernatural powers and abilities, his most common hobbies include kidnapping and brainwashing innocent people into becoming his proxies. He lives in the woods in his mansion where him and all of his proxies live.

The fandom version of Slenderman 

He is a drama queen who can not stand people who go for the "swag" look or who wear crocs. He also is somewhat self-absorbed due to his fashion sense. He often becomes overly enthusiastic about helping others find better outfits so that others can become more fashionable.
Trenderman looks somewhat his cousin Slenderman, but with a brown sweater (sometimes portrayed as a sweater vest), a white undershirt, and brown pants. His skin is also darker than Slender Man's, more tan than white.