淡淡的彼岸花香
[dàn dàn de bĭ àn huā xiāng]
Here, it refers to 'the faint fragrance of Red Spider Lily (also known as 'flower from beyond'). According to traditional folklore, this flower blooms only during otherworldly times and carries spiritual significance. Thus, the user probably wishes to convey a mystical, fleeting sensation filled with ethereal grace.