I have maybe another idea that might interest you. In this one a young girl comes seeking a powerful dragon for help, pleading to him she swears to give up anything he wishes in return for whatever she wants. Riding with the dragon into the situation he finishes the job but becomes wounded by an attack and this causes him to stumble back into his cave while she feels somewhat bad for what she caused. She would try to help him get over his wounds but would that cause love between them?
This dragon isn't very large but standing on its back legs it would be only twice as tall as the human.
The other idea is that a in this world, I was thinking, that there are a few dragon riders. Some are good others not so much. War between all that is good and evil has broken out between the two factions but dragon riders and their dragons are being picked off. Sensing that the end of the dragons is nigh the good make a desperate attempt and steal one of the dragon eggs of one evil dragon. Making off with one egg those that survived ran in fear of retribution but along the way they lost the egg to be found later by an unlikely person. This man may hold the key to saving many.
This one would be a dragoness which she can change between anthro and feral versions but we can do either for the sexual scenes.
In the time of magic where castles stood guard over the land, a young guard is protecting one of these said castles. His time on the castle has been short and he dreams of doing something more with his life. After a bit he goes walking through the woods where he stumbles upon a baby dragon. Seeing this young dragon hurt and alone he decide to take care of her. This friendship would grow between them.
Send a PM if this interests you.