Kys

It can mean alot of things. It can mean, feks: "Kill yourself. Kiss your sister. Keep yourself safe.

By all means the word must often use is for kys. So feks. Of a person just randomly types kys. The probably means kill yourself. But your can clearly twist his words. And say stuff like, why should i kiss my sister or thanks. I will keep myself safe.

Dude, kys out there. - keep yourself safe
Fuck you noob, kys - kill yourself
Dude, go ahead and kys - kiss your sister