What does the last paragraph of the ten deadly sins fireworks bomb mean?

At the end of the ten deadly sins fireworks, two girls killed their counselor with a bomb, because the counselor often oppressed them to buy his products, or they would be expelled from school.

Lan Xinhui wanted to clear Xu Nian's suspicion with her own death, but Xu Nian didn't flinch. In full view, she resolutely walked towards Lan Xinhui, and the two embraced. The compass bomb exploded, killing two girls on the spot. But no one can separate them.