Toxic?

I have this friend that was my first time, and now we are just friends, but sometimes he bothers me in a flirty and friendly way, I dont know how to explain it.

Few months ago, I invited him and my boyfriend to a party together and now my boyfriend just told me that he is not feeling very well with my friendship with him, because he saw in the party that if he could still be with me he would, so he asked me if i could get my distance with my friend.

Is it toxic??