boss manassa serpent qween disapeared and my character is completly stuck

if a dev is reading pls help me .kill my character or teleport me pls

You should be able to exit to character screen, log out, or kill the game process using ALT-F4 and then click on the "House" icon next to your character when returning to that character on the Character Select screen. Hovering this icon will show "Log in to Town or Hideout."

Alternatively, on PC you can "Control-click" the PLAY button on the character select screen. You could also wait for your map to time out (which it will have by now), but you don't need to.

This should force your character to respawn into your last hideout or town instance instead of returning to your map. There will be a pop-up dialog confirming that you wish to abandon your current instance.