Fae merging to the end or?

I have a 4+9 Fae, should I not merge the last one for a possible weapon upgrade like A.Tiki? I just got the ninth so it's not like I have the last one right now, but in the future if I get one, what to do?
p.s. A little leg banner bitching xD
136 orbs, just B.Ike. I was hoping for at least 2 with this amount. But Fae got SB and Aether. That's something.