Based entirely on me reading too far into that part of the 1994 film when the girls kiss their mother goodnight and Jo's is more of an 'Eskimo' kiss. Or Kunik, or whatever name you know it by. Which spiraled into an autistic Jo headcanon
Canon divergent of course
Jo was a wild, squirmy baby who would not stay in one place, ran so fast on her little legs even though she often took tumbles, and couldn't stand kisses. Her mother quickly learned that. She thought Jo would grow into liking them. She was such an affectionate baby in any other way, through hugs and babbled words.
She never did grow into them, at least not in the traditional sense, but Mrs. March soon realized that when her baby bonked their foreheads together, she did it the way a cat might, not to be mean. So she caught little Jo's face in her hands and taught her to go gently so she wouldn't bruise her forehead.
All of her other daughters were perfectly content with pressing their lips to their mother's cheek, or clumsily planting one at the corner of her mouth when they were small and wobbly and off-balance. Goodnight kisses remained, for Jo, the touch of noses, which was close enough.
Mr. March braced himself for impact with a huge smile on his face. His girls, as soon as they saw him, rushed all at once. Amy clung to his legs, Beth tucked her face in his jacket, and Meg touched his face, taking in the new creases around his eyes. Her father looked older.
Then came the enthusiastic bump of Jo's forehead against his, and he laughed. He returned the unconventional 'kiss', something he had not gotten to do in years.
Meg could see Jo biting down on the inside of her cheek, valiantly attempting to hold back her tears. She had made it past the vows and the first dance without crying. The bride smiled somewhat sadly, taking her sister's hand.
"It's okay if you want to cry."
Jo leaned forward, pressing her forehead to Meg's. "I'm so happy for you," she said, through mingled tears and laughter. "Even if you are leaving."
"I'll be just down the street," Meg laughed. "It's not as if I'm off to Europe, like Amy."
"I know." Jo looked over Meg's shoulder. "I think John wants another dance. You should join him."
"Of course, I'm just being silly. I'll be back to my regular self in a few minutes. I'm going to have some more cake!"
Laurie's lips touch hers.
Jo jerks back as if burned.
"Why did you do that?" Laurie sounds indignant.
"You know I don't like being touched there," Jo says, in a daze. Laurie knows this. Everyone knows this.
"I thought you might grow out of it someday. Jo, we've grown up. And I love you, and I promise we really could be happy together..."
Jo is never inclined to say yes. Later, she rubs her face against her pillow so hard, that her lips go numb. They dry out, then crack, then bleed, and the uncomfortable feeling still has not gone away.
Of all people, she never expected him to cross that line. It hurts more than her bleeding lips.
"I try to be willing, Jo. But I know I shall be homesick for you, even in heaven."
Beth can see the dam crumble, and when Jo bends to press the tips of their noses together, she can feel her sister's tears on her cheeks.
"I will miss your odd kisses, Jo," Beth tries to make light of the situation. "You'll have to give Marmee extra for me when I'm gone, okay?"
Jo can't find the words to speak.
"I thought you might be mad at me."
Amy's fears disappear, swept away like the sandcastles they had built as kids when she feels the familiar bump of foreheads and noses. Jo pulls back and grins. "How could I ever be mad at you?"
"I had always thought of Laurie as yours."
"He was never mine. He was just... one of us. And now he is yours. How does it feel to be a bride? Was the wedding romantic? Were the vows very long? I wish I could have been there..."
"To catch the bouquet?" Amy teases, and her sister- Jo March- actually blushes. Interesting...
"I don't believe I want to be married," Jo had told her mother one day, "Because he'll want real kisses and I can't give those without feeling awful in my skin."
"Who says your kisses aren't real?"
No one would tolerate a wife who couldn't give affection in normal ways. Laurie's proposal had been proof. No matter how much a man pretended to be okay with her aversion, Jo knew they would always want more, would always want the one specific thing she couldn't stand if only for the fact that she wouldn't want to give it. She had tried desperately to grow out of it, but no matter how much she liked a person the thought of mouth-to-mouth contact remained unbearable, as did mouth to anything contact, that's just the way it was.
So she tried not to get her hopes up.
It got hard when a certain professor made her heart skip beats.
Dew glimmered on the grass. The morning was cool and cloudy, and the perfume of flowers from Mr. March's garden permeated the air. It was the perfect day for his daughter's wedding. Mrs. March watched Jo beam as she walked up to join her father and her very-very-soon-to-be husband. Beth's piano had been moved close to the window, and Laurie was playing one of Beth's favorites. Friedrich clasped her hands in his own when she arrived. The big bouquet that Amy had carefully arranged got squished a little, they were standing so close together. The couple had eyes only for each other. Mr. March wiped his eyes not wanting to get salty tears on his book, then cleared his throat to get everyone's attention. Laurie jumped up and discreetly took his place in one of the chairs on the lawn. He grinned at Amy, one of two ecstatic maids of honor.
"Dearly beloved, we are gathered here today to join this couple in holy matrimony," he began, only a slight tremor in his voice. "You know, the first time I saw you two together I suspected this would happen." Jo muffled her snort of laughter. Her father had been the most shocked that day they came in from the rain, dripping wet and over the moon.
"Let us Pray, Lord, bless these two who stand before you. Guide them in their journey together as husband and wife." There was a brief moment of silence before Mr. March turned to Friedrich. "Now, repeat after me. I, Friedrich Bhaer, take thee for my lawfully wedded wife, to love and cherish, for better or worse, for richer or poorer, in sickness and in health. From this day forward for as long as we both shall live." He muttered the words and Friedrich repeated them loud and clear, meaning each one.
Next was Jo's turn. "I, Jo March, take thee for my lawfully wedded husband, to love and cherish, for better or worse, for richer or poorer, in sickness and in health. From this day forward for as long as we both shall live."
Mr. March smiled. "Emil, may I have the rings?"
Emil pushed them into his hands enthusiastically. "Are they married now?" he whispered.
"Almost," Mr. March whispered back. He handed over the rings. Jo slipped one onto Friedrich's finger, and he, hers. As soon as they were finished they had taken each other's hands again, tangling their fingers together. "I now, by the authority committed unto me as a minister, declare you husband and wife. You may seal your vows with a kiss."
Friedrich stooped to kiss his wife gently on her forehead. When he pulled away, Jo was smiling at him, tears in her eyes. "I love you," she whispered.