This is Teen Wolf X TVDU

This means that after Bonnie left cuz of the Armory hunting her, she goes to Beacon Hills

S7 of TVD is S1 of teen wolf

For the teen wolf timeline, we're at where Theo Raeken has come to town

so after void stiles

Bonnie is going to Mystic Falls on a visit when Klaus is at her house

He can come in because she died and never upgraded the will

they talk

Klaus wants her to teach her daughter

(Yes this is a Bonnie x Klaus story)

and shit goes down when Bonnie goes to New Orleans 

like Stiles and Scott not telling her about the new danger that they're facing

Which is dread doctors and Marie (Allison's doppelganger great something grandma)

Also Bonnie is pack mom

Derek is pack dad

They had a thing together.