How to use やつ (yatsu) in #japanese:
https://www.youtube.com/watch?v=ROcSmpXFEn8
It's often heard in #anime when referring to someone annoying, usually in the combined form あいつ (that guy) or こいつ (this guy).
やつ can be made plural too, as in Urusei Yatsura (うる星やつら).