When Tom fully became a stallion, he climaxed. Lucy, unprepared, got a mouthful then, as she broke off her blowjob, a faceful and a chestful. She was momentarily stunned. Then she swallowed. She used her arm to wipe off her face. Equine bodily fluids ran down her chest. She looked at Tom, now a magnificent stallion. Lucy wanted to be fucked so badly right now. She ran a hand down her semen-coated stomach and between her legs, using Tom's fluids as lubricant.
Tom was physically all horse, but had enough of his human faculties to recognize what Lucy was trying to do. He lowered his head between her legs and pushed her hand away. Then he slipped his equine tongue inside her. Lucy moaned and spread her legs wider. Tom wasn't penetrating her the way she desperately wanted, but this would do. She stroked his muzzle with her hands as Tom pleasured her in seemingly the only way he could after his transformation. He continued until his tongue caused Lucy's back to arch. He buried her face in a handful of straw to avoid screaming out with pleasure.
Afterwards, Tom lay down beside Lucy. She lay there for what seemed like forever waiting to recover her composure and her breath. Finally, she snuck out of the barn and to the nearby pond. She waded in and washed the traces of her elicit encounter from her body. The afterglow began to fade and the reality set in. Her and Tom would forever be apart as species more than class and social standing had ever divided them as humans.
Lucy returned to the stable, brushed down Tom, kissed him on the snout, put her dress back on, and snuck back into her room in the mansion.
The next morning, Lucy was late for breakfast. She had dreamed of two horses, a stallion and mare, running free. She woke feeling more longing. At the breakfast table, Lucy fumed silently when mother gloated "that no-good stable boy" was missing, probably run off. She was always patronizing to the help, but Lucy felt she was especially denigrating toward Tom. Lucy had no idea her mother had any role in Tom's transformation.
When Lucy left breakfast, she returned to her room only briefly, then made her way to the stables. She found Tom in the stall where she'd left him the night before. None of the other workers were around. She didn't both with a saddle or bridle. Nor was she about to ride side-saddle. Lucy got astride Tom, and gently nudged him out of the stable. Horse and rider set off on a slow walk away from the stables, past the farm fields near the family mansion, and then down a wooden lane. Lucy urged Tom on, and the new stallion steadily found comfort in his new hooves. As he moved fast, Lucy's legs clung tighter. She was wearing nothing underneath her dress, wanting that intimate touch with Tom's body. Soon Tom was racing along through the countryside, Lucy clinging to his mane, legs tight against him, feeling ever little dip and crest and hoofbeat in her. She cried out with joy, screamed with pleasure, confident nobody was in earshot. She orgasmed and again from the powerful beast. Finally, gasping for breath and fearful she might slump off the horse, she muttered a few words in Tom's ear and he slowed. Turning off the trail they had been on, he made is way to a small, grassy glade. It was a small pool of warm sunshine amidst the cool shade.
Lucy carefully slipped off Tom, and lay on the grass while Tom nibbled nearby to recover some of the energy he'd spent in the run.
Lucy watched Tom dreamily. She still wanted to be with him. Their ride this morning had been fantastic beyond words. Lucy gazed longingly at Tom's horse cock. She had loosened up quite a bit from being bareback, but enough for...that? She had tasted him the night before, and he had pleasured her, but it wasn't enough. She wanted Tom to mate with her, more than she had wanted anything ever before.
Lucy got up and stripped off her dress. Then she got on all fours, her ass pointed at Tom. She made some horse noises.
Tom stopped nibbling on grass and looked at her. He didn't understand what she was doing. Then she rose from her knees, but remained on all fours. her as was in the hair and she shook it at him. He could see her glistening womanhood. Tom strode over and licked Lucy, just to be sure. She didn't flinch.
"Please, Tom..." she begged.
Tom walked over her, trying not to step on her fragile human feet and hands.
Lucy felt it rub against her wetness. She rubbed back, slowly enveloping the head. So big! And this was her first time. She'd broken her hymen horseback riding years ago, but she'd never had sex before other than the intimate encounter in the stable last night. Yet here was the first cock to ever penetrate her vagina, and it belonged to a horse. It seemed to big, and then Lucy seemed to stretch enough to fit it. Tom pushed, she pushed, the process repeated. Little by little, Tom was fucking her. Lucy leaned forward then back, trying to emulate a thrust. Then Tom pushed harder and Lucy let out...a neigh?
Had she just made a horse noise? Lucy glanced at her legs. Were her tonenails darker? Were they...hairier? Was whatever had caused Tom to transform also transforming her? The thought excited her. She pushed back against Tom and he thrust harder into her. Lucy could feel her arms lengthen slightly. What had been slow, experimental intercourse now became something else. Faster, harder, animalistic. Lucy's shouts urged Tom on.
Perhaps true love conquers all, or the witch had not been entirely forthcoming about the spell she provided Mrs. Hudson, or simply that Lucy ingesting some of Tom's bodily fluids immediate after his change cause the spell's effects to carry onto her as well.
Whatever the case, as Tom's seed filled Lucy, the new mare glimpsed the word through fresh equine eyes. She knew now her and Tom would be together after all, and she would carry his babies, her human mother be damned.