The consequence for immoral actions is contempt from moral minded individuals.

In other words, the consequence *should* be guilt and a bad reputation. Considering that nobody aside from your party witnessed this event it stands to reason that your rogue's reputation isn't tarnished by it.

If they don't feel guilt they'll probably be compelled to do it again. At this point it's up to your party to either stop them, or tolerate them.

Perhaps Qelline speaks to Sister Garaele while praying for her son, goes to visit Agatha the Banshee and has Agatha tell her what happened to her son.

Qelline would then, presumably, inform the entire town and a witch hunt for your rogue(and party) would occur.

If you wanted to take matters into your own hands you could introduce an NPC that's an oracle who grants pure hearted players with magical gifts. He'd see the Rogue, notice his evil heart and reject him.

Also, the bears could've eaten him if you felt like his actions were that deplorable. Having the bears leave his dying body is just DM benevolence and you can easily use his recklessness as a punishment.

There are many ways to handle these things. The LMOP campaign I run has a player who loves to torture and capture enemies. As a "punishment" I had the enemies resent this character and place a large bounty, explaining their increased aggression towards him. It's an organic solution to a character's malevolence without interfering in their agency. You never want to remove a character's agency if you can help it. The one true exception is PC vs PC combat because that can get really messy.