IENFH-010 - My Sister Said 'Just Rubbing is Fine' but We Ended Up Going All the Way

Caught red-handed by his sleeping sister, the protagonist finds himself in an awkward spot. To keep things from getting weird, she offers a 'hands-on' solution. But when the temptation of her gym clothes becomes too much, the line between 'just rubbing' and raw, unprotected penetration completely disappears.