Fates of the Bride of Fire's Suitors (Spoilers Extended)

Child of three, they had called her, daughter of death, slayer of lies, bride of fire. So many threes. Three fires, three mounts to ride, three treasons. "The dragon has three heads," she sighed. "Do you know what that means, Jorah?" -ACOK, Daenerys V

As a "Bride of Fire" it seems somewhat fitting that Dany's husbands and consorts all seem to be burned at some point.

Note: I included not just husbands but also paramours and characters who seek to marry her

Drogo (funeral pyre)

Dany does kill Drogo with a pillow before this, but he is still burned and probably instrumental in the eggs hatching:

And now the flames reached her Drogo, and now they were all around him. His clothing took fire, and for an instant the khal was clad in wisps of floating orange silk and tendrils of curling smoke, grey and greasy. Dany's lips parted and she found herself holding her breath. Part of her wanted to go to him as Ser Jorah had feared, to rush into the flames to beg for his forgiveness and take him inside her one last time, the fire melting the flesh from their bones until they were as one, forever. -AGOT, Daenerys X

Quentyn (dragon flame)

Burned by Rhaegal:

When he raised his whip, he saw that the lash was burning. His hand as well. All of him, all of him was burning.

Oh, he thought. Then he began to scream. -ADWD, The Dragontamer

Hizdahr

Unknown what will happen to him, but after the look on his face during the dragon attack, it would be a fitting death imo:

"Oh, gods," moaned Reznak, "he's eating her!" The seneschal covered his mouth. Strong Belwas was retching noisily. A queer look passed across Hizdahr zo Loraq's long, pale face—part fear, part lust, part rapture. He licked his lips. -ADWD, Daenerys IX

and:

She wondered if Hizdahr was still king. His crown had come from her, could he hold it in her absence? He wanted Drogon dead. I heard him. "Kill it," he screamed, "kill the beast," and the look upon his face was lustful. -ADWD, Daenerys X

Its possible Victarion will kill him (possibly while riding Rhaegal?)

Moqorro had seen that in his fires. He had seen the wench wed too, but what of it? She would not be the first woman Victarion Greyjoy had made a widow. -ADWD, The Iron Suitor

Victarion

This quote is often taken as Victarion's death:

The black priest bowed his head. "There is no need. The Lord of Light has shown me your worth, lord Captain. Every night in my fires I glimpse the glory that awaits you." -ADWD, Victarion I

Young Griff

If Dany and Young Griff battle in the Dance of the Dragons II, its possible that Dany could burn/roast Young Griff.

bodies locked together in lust, writhing and rolling and clawing. Through curtains of fire great winged shadows wheeled against a hard blue sky. -ADWD, Melisandre I

Euron

Euron as the false AA/god/etc. is a lie that Dany must slay:

From a smoking tower, a great stone beast took wing, breathing shadow fire. -ACOK, Daenerys IV

Xaro

While Xaro is obviously not heterosexual, Qarth has joined the Slaver's Alliance against Dany.

When your dragons were small they were a wonder. Grown, they are death and devastation, a flaming sword above the world." He wiped away the tears. "I should have slain you in Qarth." -ADWD, Daenerys III

Daario

Similar to Xaro, there is no real evidence pointing toward Daario's demise via dragon, but it should be noted how bold this man is. He may try and mount Viserion to prove himself worthy of Dany.

Daario might whisper words of love when the two of them were as one, but she knew it was the dragon queen he loved. -ADWD, Daenerys VII

Jon Snow

I don't expect Jon to die via dragonflame, but it should be noted that Jon will likely be resurrected in a ritual that involves fire and stone dragons.

TLDR: The fates of all of Dany's potential suitors could end via fire/dragon.