What do you think about me telling a girl on my language learning app that she's ugly, even if I have a girlfriend?
Do you think she is ugly?
Yes, I think that she's ugly because I have a girlfriend.
It is wrong to flirt with people when you are taken. You should not contact other women online because your gf might get jealous.
It doesn't matter, it is not like I will be talking to her again.
While it is good that you don't plan on talking to this one girl again, you should be careful about talking with other women online while you are in a committed relationship. It could cause problems in your relationship.