Finding Bleu & Getting Her to Join
There's a side quest you're able to complete in Breath of Fire 2 that allows you to recruit Bleu to your team. For those out there who played the first game in the series you may remember Bleu; she's a reoccurring character much like Ryu and Bow are.
You'll be able to recruit Bleu to your party any time after you get the Whale Whistle that lets you ride around the world map on Grandpa the whale. To begin the quest for getting Bleu to join you; you'll want to travel to the part of the world that's south of HomeTown, TownShip and Coursair.
It's also the same land mass that you can find the Thieves Tomb on as well as Highfort.
On the southern portion of this land mass you'll find Thieves Tomb which is a large building located in a desert surrounded by mountains and a river. On the other side of those mountains you'll see a weird symbol in the desert. In both of the pictures above I am standing near this weird symbol on the desert. The location on the map is where you'll want to go and if you enlarge the other picture you'll see the symbol in front of Ryu that I am talking about.
Step onto this symbol and you'll be taken to a building with three different spirits for you to talk to. Raid the dressers in the back room and make sure you speak with all 3 of the spirits at this location! After you're finished you'll want to Warp to HomeTown.
Once you're back in HomeTown you'll want to visit the Magic School - seen in my screenshot above. Head inside of the school and up to the second floor. In the western most room you'll see four students and one teacher. Speak to the students in the back of the class room and one of them will reveal themselves to be Bleu!
Bleu is an offensive magic user much like Nina - she joins your party at level 35 with a full set of appropriate gear for that level.