Mommy is mad at you for not practicing your "stamina"... and by stamina she doesn't mean endurance running, no, you actually know very well what she is talking about! It's your sex endurance! She was adamant about it: you have to learn how to delay ejaculation otherwise no girl will even consider you for a long time partner! But you've been slacking off and now she insists on you starting practice immediately! She'll help, of course, she'll give you a "hand" at first, and if you do well enough she'll give you the advanced training! Fucking her open mouth, shoving your cock down her throat and, let's not forget, Mommy's Pussy needs work too! You'd better not cum to soon, Mommy really hates being let down like that... And now it's time to show what you can do! Mommy's waiting!