I recently got two male guinea pigs for my senior guinea pig, whose cage mate died in March. Right away during the bonding time, my senior guinea pig (Coco) started humping and nibbling the other guinea pigs. Since nothing out of ordinary was going on, I continued with the bonding process and put them all in one cage. Then, things started to get worse. Coco would go into the other guinea pigs' hideys and hump them and bite their ears. He would climb on top of them and put his paws on their faces. The other guinea pigs' reaction to this was to either run away or chatter teeth& lunge at coco. Through the next couple hours, I had to go back and forth from separating coco to reintroducing coco to the other guinea pigs. I noticed that coco was repeating specific things: he would go inside the other guinea pigs' hidey, hump, mount, and bite them, run out after the other guinea pigs' chattered at him, then go to his own hidey. After a few seconds, he would slowly make his way back to go inside the other piggies' hidey again. This whole process would repeat and repeat until I separated Coco from the poor stressed out piggies again. Since these new piggies are still not used to their new surroundings, and are very stressed out, I don't want Coco to add onto their stress. I am worried about the future, as I planned for the three of them to live together. Coco only seems to act up when he senses the other guinea pigs. I am overwhelmed with what to do, but for now, I just want the new guinea pigs to de-stress. Can someone give me advice on what to do from now on? I'll try to post updates on Coco's behavior with the new guinea pigs.