He is the second character to hurt Splendid without the help of Kryptonut, the first being Nutty in Class Act, and the first to do so intentionally.
He, like Splendid, may be vulnerable to Kryptonut.
Splendont's name has likely been based by the "to do" auxiliary "don't" since Splendid's name ends with "did".
Despite having only one appearance, he appears a lot in fan-fictions, and as is to be expected, most of these involve him and Splendid.
Design
Splendont may be Splendid's evil doppelganger (Likely because he has inverted colors of Splendid himself).
He could be a reference to Bizarro, Superman's evil counterpart.
He and Flaky are the only red characters in the whole Happy Tree Friends franchise. Although, Splendont is a member of the Ka-Pow! series, so that makes Flaky the only red character in the main show.