Plz i need advice girls and dudes alike?

alright theres this girl i met a coupel weeks ago i think shes really sweet i like her alot but recently i found out she has a boyfriend but there not very serious but anyway im backed up into a corner if i tryy to aks ehr out i shall be smited by teh boyfriend but if i wait they might get serious tehn i wont have a chance or do i just move on