Moldova is ethnically and historically tied to Romania - both are Latin nations.
Watch this start a chain reaction with the “Bucharest 9” (except Hungary perhaps).
If Moldavia is taken by Russia, Romania won’t let that happen. They will go all in defending their Moldavian brothers - they have no choice.
Romania being part of NATO, this means all NATO will be forced to follow up.
At that point its 50/50 on the border of WWIII.