Pisces male friend fell for me

For starters, this pisces guy became friends with my best friend a little over a month and a half ago. We all went to the same high school but we didn't know him but got familiar with him after a recent reunion. My best friend and I decided to add him to our circle to get a male perspective on certain topics. The very first night I was asking him some questions about my situation with my fwb Taurus. One of the issues is I would like for him to take me out once in a while. So pisces says "let me take you out". It caught me off guard as well as my best friend because she kinda wanted him to be more of a friend to her. I declined but told him he could take both of us. He did. He opened our doors, he paid for everything and he was a gentleman. Afterward my best friend stated that she had a minor crush on him because of his niceness. I noticed his attention more towards me but I ignored it. We would only speak through her. He would ask her about me which annoyed her. When we all hung out he would ask me to date him around her. I told him I couldn't because of a conflict of interest but I didnt tell him about her crush. This is longer than I thought...sorry. She told me that she didnt mind if I dated him but I feel like she likes him more than she's saying. He's not really the type of guy I date and im not attracted to him but if I met him under different circumstances I woulda gave it a shot. So last night he told me he is in love with me. He asked me to give him a chance. Idk if I should tell him about my bff's crush. I dont want to put her out there but I cant date him because of that. I dont wanna hurt his feelings cause he feels like he's always friendzone or like a brother to girls he's interested in. What do I do?