Laharl and Flonne's double attack where Laharl uses his Overlord Wrath's only to have Flonne turn the energy orbs into hearts. Laharl's reaction can be summed up as "How did you...? Why did you...? Why would you...? Oh screw this!" *BOOM*
Normal Prier and Culotte's double attack. After the final attack hits, although there is no true damage to Prier, Culotte's bomb explodes right in front of her and she does not take it well.
When Alouette starts making comments to Prier how she dresses, Prier points out that she's not a position to given her outfit. The two of them then realize that their outfits were both designed by Father Salade.
During the fight with Noir, the first any character targets him, it will lead to some dialogue with him asking what they are fighting for. While this mostly leads to a a serious response (and Noir saying what he's fighting for), if it's Papilion, then she will comment "Whatever. Who cares?" Noir will reply ... It looks like I chose the wrong person to ask.