That is a lot of blood. There isn't much you can do unfortunately - maybe gently bath the area with warm water and a cotton wool pad to sloosh away any smell or staining. Don't bum-bath at this time of night though - he'll be going to bed damp. Are you able to tell whether it's from his penis or from his anus? I'm assuming penis as the first pic looks like there is also pee which has soaked in and spread as a puddle? Does he have any other symptoms? Hiding away, swollen and inflamed down below, squeaking when peeing, wet under his tummy from dripping pee?
Blood in pee has two common causes: urinary tract infection (UTI) and bladder stones (or sludge), although there are other things that sometimes crop up. Neither are very nice but one is easier to deal with than the other. They can get both together - but one step at a time! Your vet will hopefully give him a decent dose of metacam/loxicom for pain, whatever the cause. UTI is usually treated with antibiotics and if successful you should see an improvement in symptoms with a couple of days. My boy had a UTI at the end of last year and this time the first choice of antibiotic (Baytril) didn't help, but the second (Septrin) did. Your vet might also suggest an x-ray to check for any bladder stone formation - you might want to accept or you could ask about deferring this until you see what the antibiotics do. Ask about the price and whether piggy will have to be anaesthetised. It shouldn't be more than a whiff of gas (is how my vet sometimes puts it) but they may be OK with wrapping him snugly in a towel and doing a quick conscious snap. Some vets don't have a machine and might want to refer you somewhere. Or they might suggest ultrasound - but check whether he'd have to be shaved for that as he won't be happy! Bladder sludge can sometimes clear on its own with plenty of drinking but a big stone will need surgery to remove it. But it might just be UTI. Prompt treatment is best, not just for piggy's comfort but also because persistent infections can trigger stones to start forming. Your vet should get you in to see someone tomorrow if you tell them what the problem is - you can offer to send the pic in. Tell them it's a proper blood-puddle, not just a bit of a pink tint. Good luck x