This person will be someone that gets under Mark’s skin despite him being a chill individual by nature and understanding. These two will have a hatred that can’t be understood from outsiders. Growing up together these two got along in their younger days but as time goes on and they head in different directions, they seem to constantly heads.
Side note: They can be upset for a major reason or minor, ic confrontation is permitted by me and would need to be something you’ll need to be comfortable with. The outcome is unknown for mystery purposes.