Oh come on you useless whore! You can do beter than that! Give me a show, you can be sure you'll be doing worse things for your tutors so if you're embarased by this you may aswel leave now!
Pretend a gorgeous shemale will only let you suck her off if you can convince her you know how to get rid of precum.
Suck your finger like a slut for a full minute, gathering precum every 10 seconds.