What are my mandarins doing ?

[54seaweed]

Are these two doing what I'm thinking
this is the funniest thing I've seen in a while
the bigger of two was added this week
the one bites on the others tail and rides around like that

 

[crister13]

If they're both male they can't be kept together. If ones female and ones male, they could be mating. Not sure though.