Romance manga, no tragedies.
Must be completed
No One-Shots.
Preferably 2 people living togethor in the same house/apartment get togethor by the end of the manga.
Male and Female relationship, no yaoi/yuri
No smut/psychological/mystery/josei/mature
Preferably A sweet cohabitation type/ live-in lover manga that ends well.
Can be stepsiblings with no blood relation.
Maybe a slice of life

Try the Genre Search, select Shoujo and put in the "cohabitation" tag. You can also choose scanlated manga only.

Yome Ga Kore Na Monde.

Love Lucky

Bonnouji

Orange Yane no Chiisana Ie

Mahoraba