"F*ck, what's this thing?!" Fairy Lychee subconsciously stretched out her hand, and prepared to grab the 'virtuous lamia'. She wanted to let her have a taste of her unique skill, the '365 rounds windmill spin'.
But when she stretched out her hand, she wasn't able to grab anything.
The virtuous lamia had two different forms. The first one was the solidified form, where she was a solid entity. It was the form she used when displaying the 'Three Heads and Six Arms Technique' alongside Song Shuhang or when she was blocking curses or evil attacks in his stead.
Her other form was the ordinary 'light of virtue' form. In this form, she was just a mass of intangible light.
When she entered Fairy Lychee's room, the virtuous lamia was in her solid form. But now, she had switched to her 'light of virtue' form.
Therefore, Fairy Lychee's hand simply passed through her body.