Mondstadt has been destroyed because the new archon war happend.. At this time you were venti's beloved.. His partner. You laid bleeding in his arms as Morax hit you with a huge meteor. Venti was already mumbling things

"Please.. I cant lose you aswell.. I'll love you for infinitys.. I dont want you to leave me.." he kisses your bloody cheek as his huge white feathery wings spread as if trying to protect you