Soulmates/soulmarks 

On the right wrist is Leorio name
Leorio is 19 years old. 

Eri’s name is on Leorio's right wrist.  

And 

On the left is Kurapika
Kurapika is 17 years old. 

Eri’s name is on Kurapika’s left wrist  

Their soulmark burns when they hear their soulmate say their own name.