Let's look at the bottom of the table, there are 3 clubs that have the same points, Mainz, Koln and Darmstadt who have 10 points each, ranked next is Union Berlin who has 13 points. It looks like the competition at the bottom is no less interesting, they will compete and shift each other until the end of the season.
Bremen and Bochum who have 16 points cannot be said to be safe, the article with the number of matches that still exist now it is very enough to catch them, especially if they lose a lot of points.
Focusing on Union Berlin, they are a club that has failed to perform well this season, after last season they could compete in the Bundesliga top 4 competition. The decline they experienced was so sharp that it put them in the current position, in a position that is very vulnerable to relegation.