should i be this afraid of this friend?

i met a guy like 2 weeks. his name is John and he’s amazing. however his friend Lucas, is very manipulative and controlling over John. Me and lucas don’t really get along that well and everytime me and lucas fight he mentions having all the control bc he could convince John to stop talking to me, because they are really close friends. it makes me question my decision to want to be with John bc i’m afraid of Lucas’s influence on John who is more of a follower. so do i stick with John and ignore the friend or leave them both alone?