So i originally went out with a girl some months ago, we hung out, it was nice but ultimately it felt platonic. She's got a lot going on which is understandable and the next few times we've hung out we've felt like good friends. I met her friend and we got along really well, we flirted and i felt an energy i didn't have with the first girl. I've seen her on a dating app or two and i'm seriously considering asking her out at some point.

So my issue, is it a faux pas to ask out this friend of the first girl? I feel the issue could be that the first girl is offended as we first met through a dating app and unbeknownst to me perhaps she may feel there is still potential? Any advice is appreciated.