From the GCC presentation, they flashed a slide showing that Rose the Spirit will be an RNPC in the future!
It has been said that Duke Felipe planted 2 special roses in his garden to remind him of Grandice, for she had hair as red as rose petals. Maybe he really did love her after all... However, after Montoro had taken ownership of the Lucifer Castle and tampered with the roses for the cloning of Grandice, the roses metamorphosed into rose demons. Made from the thorn of a rose, emerged Rose the Heart, and from the petal of a rose bloomed Rose the Spirit.
Also, I read somewhere that Soltiegus, the demon that takes on the form of a little girl, detests women with red hair. Unfortunately I lost the picture stating that piece of information. Probably Grandice has got something to do with that. If only IMC disclosed more story on the bosses residing in the Lucifer Castle/Gardens... it will be an interesting read.
Speaking about Duke Felipe and Grandice, sometimes I wonder if Claire ever thought of tracing her origin to find out who her biological parents were... I mean it's only natural to be curious about it. But anyway, IMC needs to weave more follow up stories on my darling Grandis too! I would also like to know the story behind Catherine's mother.