The one who originally got the spear is Tao Xiurong, she is the original owner, and being the first and original owner, she can somewhat decide who the right person should be that can take the spear.
The spear originally chooses its owner on the basis of how much good and bad deed one has done and how strong his resolves are for his goal.
And the spear knew it, the moment Chiyou came closer to it that he should go under the command of Chiyou, but
Tao Xiurong prefers someone good-looking, not someone like Chiyou who looks like a demon.
She gave her command or desire, and so the spear chose the owner of her liking and also someone who is ideal to use the spear.
. . .
"What is the meaning of your action, Prince Xiong Bo?" Chiyou asked as he looked at Prince Xiong Bo
The moment Chiyou pulled the spear out, the spear started shaking and got out of his hands.
