Whereas Yuya thinks 'friend' is better, Strange frowns a little before shaking his head. He doesn't think that friend's a good choice of words at all.

"If I say I'm his friend, then Lambert and the Ringmaster will just start yelling at me again. 'He enthralled you, you can't be his friend' or something like that. At least with ally, it doesn't presume any feelings of that sort."

Besides, Strange still doesn't really know what he feels about Ignatius. He wants to show a bit of compassion and help him deal with these new circumstances, but 'friend?' Strange isn't too certain he wants to go directly to friend.