Chapter 1: criminal L

Jean gave Eren a gift a beautiful Red Ruby Earing. Eren gladly accepted it happily loving Jean, but not knowing what the consequences were.
A Criminal calling himself "L" want the earring badly and will do Anything to make it his. Knowing that Eren has it what will happen to Eren when L gets his hands on him?
Can Eren leave Jean so he can be with L or will L end up not caring about Eren and leave but taking the ruby with him ?