But in The Book Of Lost Tales, there is a character called Tuvo, who always pulls my attention in the earlier versions of his story.

A and B call the wizard-king Tuvo, not Tu; in C he is not named, and in D he is Tu 'the fay', as in the tale. Evil asso- ciations of this being appear in A: 'Melko meets with Tuvo in the halls of Mandos during his enchainment. He teaches Tuvo much black magic.' This was struck out, and nothing else is said of the matter, but both A and B say that it was after the escape of Melko and the ruin of the Trees that Tuvo entered the world and 'set up a wizard kingship in the middle lands'.

Tuvo is rewritten and becomes Tu. A fay (the Maiar had not been conceived yet, Melian is also called 'fay') with strong magical power, who became a king among Elves who never left Palisor. He does not stand with Melkor. He is a protector of elves and men and ensures their safety when Melkor sends his agents.

All those versions are abandoned.

But I do wonder if the early versions of Tu/Tuvo's story were reworked for the early version of Sauron's story as we read it in The Lost Road:

Sauron was the chief servant of the evil Vala, whom he had suborned to his service in Valinor from among the people of the Gods. He was become a wizard of dreadful power, master of necromancy, foul in wisdom, cruel in strength, mis-shaping what he touched, twisting what he ruled, lord of werewolves: his dominion was torment.

Maybe I'm also affected by the name because, despite the fact that Tu/Tuvo 's character did not make it past the Book of Lost Tales, it also makes aesthetic sense lingustically that the name can be associated with 'Thu' and 'Gorthaur' (and therefore with Sauron's character).

Y en ese preciso momento sabrás que yo fui lo mejor que tuviste en tu vida. Que nadie te amo como yo lo hice; que mis besos eran el cielo en tu marchita vida, que yo creaba poesía sobre tu piel vacía, que mis caricias eran el pasaje al paraíso... Y es que definitivamente, yo fui y por siempre seré la que más te ha amado.

No, no niego que yo también te he extrañado, que anhelo fervientemente que vuelvas, pero quién se fue, ya no regresa; y si lo hace, jamás vuelve a ser lo mismo porque el amor real se fugó del corazón.

[ID: Grayscale digital art of six characters from Middle Earth. On the top row are Nuin, Daeron, and Legolas. On the bottom row are Tuvo/Tu, Luthien, and Tauriel. Each character is shown from the shoulders up and looking forward. Nuin has shoulder length hair. He has multiple scars on his face, including one that goes across his nose, a bite mark on the side of his face, and slash marks on his throat. He has a plain tunic and a thin, patterned vest. Tuvo has a tired expression, a wide-brimmed hat, a dark tunic, long hair, and a wide, patterned vest. Daeron has dark hair, which he wears in an afro. He is wearing a terleg. Luthien has her hair dark in box braids and is also wearing a terleg. Legolas has dark, wavy hair which is contained in a ponytail. He is wearing a patterned tunic that closes at the front and has a collar. Tauriel has straight, dark hair, which is worn in a braid. She wears a similar kind of clothing to Legolas, though her has a darker background and light patterning, while Legolas’s is the opposite. End ID]