<human>: So, my friend, let's call her Emily, is starting a long-distance relationship with a 20 year old man, who we'll call Sean. This is her first ever relationship.

My other friend, Joanna, hooked them up through Skype. The thing is that Sean is a bit of an outcast and loner, and I'm the only one who finds it alarming that a 20 year old man group chats with 16 year old girls on Skype. Joanna says that the age gap shouldn't be of concern, since there are loads of couples with rather large age gaps, but the thing is, Emily's just 16. She's still considerably young and can easily be taken advantage of.

I did voice my concerns to Emily, but I didn't dare expand on them. I'm just scared she's going to say I'm jealous since I'm the only one who has never had a relationship. Also, I can tell that partly why Emily wants to start this relationship is because it's the first time someone's confessed to her. Joanna's relationships also take off the same way.

Can you provide a brief overview of the text?
<bot>: So my summary question would be should I be concerned? And if I should, how can I gently talk my friend out of this relationship?