Bros, you have to be careful.
first, get her sloppy drunks on the rum you keep next to the bed.
next, get the place dark, and throw some pre-planned lez porn on the ipad to distract her.
bend her in a fckable angle, and quietly hock a loogie on it to lubricate suddenly. use your fingers and give her that fake 'going down' without ever putting your lips and mouth to the nether region where a million dudes' unwashed junk may have gone before. play with her ass and she may shift it to 'let's get to fcking'.
be brief, wet it up, but for gods sake don't do down. and if you do, you better mouthwash with that rum FAST afterwards!