Her

 She knocked on the door to the apartment I shared with a friend

I answered the door and let her in

My roommate had a date

My roommate my best friend

Together they left

Me alone once again

But wait

That look in her eyes when I opened the door

Was see telling me something

I'm crazy, she's my best friend's gal

but still

what did it mean

I wont deny that I liked her

Maybe a little more than I should

But this is my best friend we're talking about