Love... After the Fighting Is Over

Having finally arrived in Celestia, our heroes discover that Vulcanus was responsible for the attack on the Netherworld. Upon meeting with Seraph Lammington, the trio learns why Flonne was sent to kill Laharl's father and wake Laharl. However, despite the Seraph's kindness, Flonne is still punished for her sins of hurting Angelic Soldiers.

Synopsis excerpt via Kitsu.