Snail gang war or Snail Orgy

Ok I don't want to abuse the ASAP forum but this is odd. I am a new reefer tank cycle has been good. Over 2 months now and have 1 damsel and 1 toadstool in my 24g nano. I have a cleaner crew adn everything has been solid. Tonight i get home and noticed my toadstool was not right. I look down and see my 3 Large Nerites tumbling around and pulling at something. They were going nuts. Looking like they were trying to have sex with something. IDK if that is a pink tounge or what. I am not trying to be vulgur here so I appologize for my lack of knowledge. I recieved some more snails today for my cleaner crew. I got some Dwarf Ceriths and 5 Fly Speckled Cerith. Well the Large Nerites were attacking 1 of teh Speckled Ceriths. Is this normal? The were all over the one. I pulled it out of the tank and now the large nerites look like a gang looking for the others. Please advise..

 

They are probably just hungry and wanna eat somthing