Dyuuuum, how could this be understood?
When Yuyan spoke, Yino felt as if a living Buddha had descended.
Compared to the shock of sharing a bed last night, Yino was gradually getting used to the changes in Yuyan's attitude. Though it seemed far-fetched, ever since Yino pretended to lose his cultivation, Yuyan had become noticeably gentler towards him. Her words and actions all but wrote her favoritism for Yino on her face.
The level of intimacy was developing so quickly that even Yino thought it was too fast. He had originally planned to completely win Yuyan's heart when her destined plot point arrived...
But now, Yino was experiencing one of life's three great delusions - that Yuyan had fallen for him. Otherwise, how could a normal senior sister, upon waking to find Yino's obvious morning condition, not only avoid suspecting him of doing something sneaky last night, but also show no anger? Instead, she was gentle and calmly patted the bed, inviting him to sit beside her?