Why is he using Tinder?

[Anonymous]

I saw a guy I know on Tinder, he is in a international relationship with someone that lives on another continent and has just arrived home alone on Thursday after spending 8 weeks in her home country. I know he used it recently and not forgot to delete it as he has uploaded pictures from his time in that country. I'm surprised to see him on Tinder as they both post pictures of them and seem very in love. Should I tell his girlfriend? Why is he using Tinder?

Updates:

[RemoErdosain]

Well, it's pretty evident that he's having his fun while she's away. Not everything is what it seems (as for them "looking" in love). You should totally tell the girlfriend, and show her screenshots if you can, to warn her about what she's getting into. I would've really appreciated if someone would've warned me about my ex before I found out by myself a year later. That's the problem with long distance relationships: Cheating is so much more frequent in them

[ManWithThePlan123]

Well he's probably filling a physical need that he has. I don't know if telling his girlfriend really will help but you can try it out.

[Wise4myage]

I say stay out of it because they might have some sort of agreement (that you don't know about) where both of them are allowed to date others.

[007kingifrit]

what country is he from? what country is she from?