You can wash your bedspread with a detergent soap. Soak the bedspread in water with the detergent for a few minutes and then gently wash the bedspread and especially the stained part. Rinse off the soapy water from the bedspread and if the stain is still visible, repeat the process until it is all gone.
If it's washable it'll come out when you wash it. You're folks shouldn't be too upset, as it's washable, don't try to hide it that might end up getting you in more trouble than to begin with. Good luck.
You may first want to try a Tide Stick stain remover before you do a full blown wash in the machine. Man they work well!! It took off red tomato stain off of my white jacket. I got my Tide Stick at Walmart. Smiles Grandma