So far I only agreed to meet the guy do I need to go back?, the guide warned of calling it a scam
I believe i understand the rest if there is nothing I need to look out for.
If by the guy you mean Ken, it's alright for now. You'll have the option to share Anna but you don't have to. You can bang his MILF Samantha so I won't recommend to go back/ ignore his quest.
Just a heads up, if you want additional scenes with Samantha then you'll have to share Samantha with Ken. You'll have solo scenes with her but to progress Ken/Samantha arc, you should share her, but the choice is yours.