It attacks the Himalayan Branch without paying attention to Godot Valentine who tries to accost or distract it. However, the Protagonist is able to catch its attention and stop it from attacking the Branch.
As for the origin of the name, Kubera is a Lord of Wealth and god-king of Yakshas in Hindu Mythology. Kubara's usual depiction is plump body, wearing anysort of jewel accessory, carrying a pot full of money and a club. Read more about Kubera's details here.