What's wrong with my bean plant, /out/?
If you're into the no pesticide/herbicide thing like I am, just put a plank so the slugs can crawl under it when the sun starts to shine, pick it up before the night and dispose of them.
Also, if you have plant fleas watered down medicinal alcohol does wonders, vinegar is bad because it fucks up the PH of the soil.
Same problem with my beans OP but I think I have snails not slugs. They eat the sprouts the plants don't even make it as far as yours. I bought 3 bean transplants and used those instead and it's working out great so far.
It's got AIDS. Same thing happened to my carrots when my faggot neighbor snuck into my garden and stuck them up his ass at night. Or maybe the carrots gave him the AIDS? Either way they're both dead now.