lim·er·ence
the state of being infatuated with another person
It all started with this weeks glee club theme. 'Feelings'.
Rachel centric. Rachel/Puck/Sam with a pre-existing friendship.
Finn needs a favor and Rachel is the only person that can help him. Falling in love was never a part of the plan but it just happened...But some people didn't enjoy that and will try their best to break the couple.