I Can in fact finish it in 2nd day,
My unit :
Vincent Berseker For DD
Vincent Warlord For Puller and DD
Vincent Gladiator For Stunner and DD
Cybella For DD and Sleep 2 turn while waiting for skill 2 turn
and Lucille Inquistor as Healer
Also I Use Guardian Ally as Tanker and Taunt cause i dont have any Guardian
I finished it at least 39 Turn or more.