1) Shana : She was the reason I got into Shakugan no Shana. No Shana = no show IMO. And I love her melon bread love.
+10 for Shana since shes voiced by Rie Kugimiya too. I may just be a closet lolicon though...
2) Alastor : I love him in the Shana-tan Specials.
3) Konoe Fumina : Even though the episodes she were in sucked hard I still like her. It may just be Noto Mamiko like ChrissieXD said.
All the other characters are likeable just not my favorites, though sometimes I wanted to smack my head repeatedly into a wall at Yuji's density at the 2 girl's feelings. If I hated 1 of them I would fast forward to the next scene in 0.001 seconds.