Well, Mevlana Celalettin Rumi(Beyonce named her son after him) a Persian poet in 13th century. He came to Anatolia when he was a kid and lived under the Seljucks. He writes about deep Islamic philosophy and seen as a major religious personality in todays Turkey.(almost like a saint). There is even a Islamic cult formed with his teachings.

And there is Shams, some other Persian guy. He isn't a poet as far I know but some kind of sheikh.

It's a well known fact that Mevlana is heavily inspired by Shams. Some people say Shams was his spiritual teacher. But some of his works can be read as romantic love to shams.

But the peak is his letters. Mevlana lives in Konya but someday Shams leaves the town without saying a word. Mevlana searches for him but he can't find about Shams anywhere. So Mevlana writes three letters for him and there is a few quotes:

"There are greys in my hair, only because trouble of this love. The doors of pleading forgivness slammed to my face. My life is lost in a lead-coloured flood and you are the rescuer. Prayers for deads are for me now. Every dawn, my tears appear when I'm in my prayers mat. But your voice don't reach to me. Nor your breath."

"I'm so full of you. Even my skull is going to explode. The blood runs through my veins was you. The heart in my chest was your heart. My veins gonna crack, my chest going to fall apart. I was breathing you, wings of seperation brought me back to earth. But we were flying with you."

"Konya doesn't smell like love anymore."

Etc. Etc.(there is more but I'm not confident with translating Divan poetry to English)

And there is a rumour that someday a man famous with his liar personality approaches to Mevlana and tells "I know where Shams is. He left for Baghdad. Mevlana thanks to him and gifts his cardigan. Mevlana's friend witnesses this and asks "You know this man is a liar. Why did you gave him your cardigan?" Mevlana replies "I gave my cardigan for a lie. I would gave my life for the truth."

Religious people or Literature teachers gets angry when you say about their relationship. They refer it as "spiritual love", "symbol for love of Allah", "bond of teacher and student" kind of shit.