Thank you everyone. It was such a shock. Even the girls were confused. They were sniffing him and walking on him, trying to get a reaction. I got them out of there, and then wrapped him up in his favorite red towel (when I cleaned the cage and brought him back in onto that towel, he would "dance" and then start digging around in the corner to make a little nest of it to sleep in).
The girls and I spent some time mourning his loss last night. They all climbed into my lap, even Sakura who still mostly avoids me, and I petted each of them and told them that Rokk had gone to the Rainbow Bridge, which was a wonderful place, and he would get to play all day and eat yogies and there are lots of places to climb and hide and sleep, and as much pea fishing as any rat could want. And I told them that when they go, Rokk is already over there to greet them and groom them and show them around. I'm sure he misses them and will be happy to see them, even though they didn't always all get along - I think it was more in the way that siblings don't, and not that they actually didn't like each other. I also told them not to go for a long, long time, not until they're old, because then they'll really love being able to run and jump and play like a young rat.
I buried him this morning. Wrapped in his favorite towel, I gave him a few of his beloved yogies, although I'm sure he's eating more than he should right now. I read a few times about people giving them some change to take with, to pay their toll. I originally put in 7 pennies, one for each week he was with me.. and then I thought of all the poor rats who arrive with nothing, fed to snakes or just not cared for properly, so I gave him a handful more and told him to help as many rats as he could because they are all precious and wonderful and deserve to be happy forever. I told him how much I loved him and that I would miss him, and someday I'll go visit the Bridge and we can play together and he can climb onto my shoulder and brux in my ear and I'll give him skritches and kisses and tickle the little black spot on his tummy.
Here are a few of my favorite pictures of him.
I will miss you, sweet boy.