tsun tsun~
When a Person is acting very cold towards a target, which they have a crush on. Like the tsundere archtype in chinese cartoons.
Peter was tsun tsun~ over his late invitation
tsun-tsun
The short nickname for the word: Tsundere. "Tsun Tsun" is used for cold/blunt/curt attitude, while "Dere Dere" is used when a person becomes embarrassed in front of his/her lover.
Therefore, "tsun-tsun" is a female character who is usually cold, however the "dere-dere" part is when she starts having feelings for her lover. Or, she is cold to the main character at first, but she becomes lovestruck later.
Tsun Tsun Sharkboi
Another phrase used to describe the personality of the famous VTuber TheNexusCreed.
Holy shit bro that Nexus is such a Tsun Tsun Sharkboi