Translations (JP to English)

[Zetsumei_Tsunarashi]

I think would be fine if the spell just finished as normal even if your target dies. Then you would hit in the same area you meant to in the first place. Just use the dead monster as the center for area of effect.

In current version it is already possible to target dead enemies with spells. We used to have Siphon MP and Siphon TP, which these spells were meant to be used on dead enemies, so why can't they just use this same coding ? I remember I used to time my Siphon MP so that I started casting spell while the enemy was still alive, but finished casting after it was dead for more MP. So this is already possible, dev just needs to fix it.

If you want to cancel it, for example if the dead monster was the last one in the group, you can just move to cancel it as you said.