'Emotional currency' is social interaction; the “value” you give to others and others give you to in the form of emotions.

Thank you for your supplementary explanation. Does that mean one can also save, loan or be in debt when it comes to dealing with emotional currency? For example, let's suppose I loan a friend of mine some emotional currency, such as giving a favor or something. Does this mean "The friend owes me."??? Moreover, am I right to understand emotional currency has the power similar to money?

Me personally,... I would never use this phrase. However, I agree with Jura below. I'll try to add a little detail. "Emotional currency" is referring to basically the support, or comfort people feel when you interact with them. There is some "value" to interacting with other people. For example, when I spend time with friends, I feel good because I spent time with my friends instead of being alone. That good feeling has some benefit to how I feel. In other words, it has some "emotional value". I mean, it makes you feel good when otherwise you would have felt normal/bad. I believe that is what "emotional currency" means,... the emotional benefit of something. Currency is usually used with money but,... of course, money has value. Replace "currency" with "value" and maybe it's easier to understand the nuance. Basically they have the same meaning but, currency is used for money.