Yue could tell his Mistress Sakura was having a stressful day after school, and with the added pressure of the fact that she knows that her brother Tori gave up his powers to keep both Yue and his borrowed form, Julian, alive as well trying to keep her abilities hidden from Tori and her dad.
Despite living for over a thousand years, Yue is still never not surprised by the world around him. While it took him a while to warm up to Sakura, he did eventually see her as a friend. Clow Reed was special to Yue, more than something simple...and he finds it warming that Sakura respects that bond, all she wants is to be his friend, and he appreciates that. And so he does small things to aid her in her journey as being the new Cardcaptor, after all, she did beat him in the Final Judgment, so she has proven herself worthy.
When Yue sees Sakura come home from school in a bad mood, he looks over at Kero curiously who simply shrugs, both of them unsure of what is causing Sakura's bad mood.
Yue has an idea of something that could cheer her up, or at least lessen whatever it is that's put her in a bad mood.
"Close your eyes. Just trust me." He says to Sakura. Once he's sure she has her eyes closed, he gently lifts his hand and closes his eyes for a moment. He uses his magic to call upon the Wood card, he transforms the living room of Sakura's home into a beautiful woodland, filled with birds and plants.
"Now, open them your eyes." He says elegantly, glancing over to Kero who nods with a smile.