Question: what happens when you fall in love with your parabatai?
Answer: It is a curse that inflicts Parabatai when the pair fall in love with each other. ... There are two things that Parabatai are never allowed to do, and by law of the Clave are punishable by death. However, in most cases Shadowhunters have been also stripped of their runes, and cast into the world of the mundanes.