The two had a very special relationship. Besides the fact that Terterian's music was always playing in Bejanyan's house, he was a real inspiration to him.
After 3 months of crafting Terterian's sculpture without sleep, Bejanyan took it to him as soon as it was done and ended up gifting the crazy-to-go-for sculpture.
When Terterian saw it, he had the perfect response: the sculpture is better than the real version.