These reasons below is how they contrast.
Cogsworth is the head servant of a castle and is well mannered and well dressed and teaches the other servants how to behave and run the castle, and he is overweight and kinda weak.
My OC doesnt have to worry about rules and is free spirited wild and adventurous, lives around an African jungle full of wild animals and is skinny muscular and strong and his lifestyle and the way he dresses is the complete opposite to Cogsworth.
And those reasons is why I ship them so much, I like to imagine they get along very well spite their differences.
:EDIT: Also while Cogsworth knows every detail about the castle his friend knows everything about in and around the African jungle he lives in and how to survive there.
Here is my Journal Entry about my OC.
My weird OC's and headcanons :D Headcanon 1 For some reason just for the fun of it I have this weird headcanon of Buck from Ice Age that he use to have a friend before he came to the dinoworld that resembled Cogsworth from Beauty and the Beast in personality and characteristics, based on my other headcanon of Buck here chippanythechipster.deviantart… about him use to live in a family acting like something of aristocrats, I imagine spite Buck not liking his family's lifestyle he was good friends with his friend that was similar to Cogsworth and he actually had alot fun with him spite him having a similar refined personality like Buck's family (based on Cogsworth from Beauty and the Beast having a fun and a bit rambunctious side to him spite his usual uptight demeanor) and he was the only one Buck loved to be around since when