One common theme is isolation. Fanfictions often depict Naruto being left out of village activities and not being invited to things. Another theme is self - discovery. Since he's alone, he has to figure out who he is on his own.
In fanfiction, Naruto's lonely childhood often makes him more determined. He has no one in the beginning, so he has to rely on himself. This self - reliance becomes a big part of his character. He's always eager to prove himself and gain recognition, which can be traced back to his lonely days when he was shunned by the villagers.
One possible scenario in this fanfiction could be that Naruto's friends all got caught up in some mission on his birthday. He's waiting for them to return, but as the day goes on, he starts to feel that familiar loneliness. He then decides to go to the training ground alone and train, using the physical exertion to mask his disappointment.
The fanfiction could explore Naruto's loneliness by depicting his isolation during his training. He often has to endure difficult and solitary training sessions. This physical and mental isolation can emphasize his loneliness. Also, in some fanfictions, his loneliness might be shown when he faces discrimination from the villagers. Despite his efforts to be friendly and gain acceptance, there are still those who shun him, which deepens his sense of being alone.
Naruto might go to the Hokage Rock and sit there alone, looking at the village below. He thinks about how far he has come and yet, on this special day, he doesn't have anyone to share it with. His mind drifts to his parents and how he wishes they could be there for his birthday. He then decides to do something good for the village in their memory, like cleaning up some of the less - visited areas.
First, understand Naruto's character. He is a complex character with a lot of depth. You need to capture his essence, especially his experiences that led to his loneliness, like being an orphan and the villagers' mistreatment. Then, create a plot that revolves around his loneliness. For example, you can have him on a solo mission where he has time to reflect on his life. Also, use descriptive language to show his emotions, like 'Naruto sat alone on the cliff, the wind whipping through his hair as he stared into the empty distance, his heart heavy with loneliness.'
One great Naruto lonely fanfiction is 'The Loneliness of a Jinchuriki'. It delves deep into Naruto's feelings of isolation as a child, before he made friends. It shows how he coped with the villagers' hatred all by himself. Another is 'Alone in the Shadows', which focuses on a time when Naruto was on a solo mission and his thoughts about being alone in the world of shinobi. There's also 'Naruto's Solitary Journey' that explores his journey of self - discovery while being lonely.
Naruto's character can also be developed by his interaction with the environment. If he's alone in a snowy landscape on Christmas, he could use his ninja skills to create something beautiful, like an ice sculpture. This would show his creativity and his ability to find joy even in solitude, and also how he can turn a lonely situation into a positive and productive one.
One aspect of Naruto's sad childhood in fanfiction could be his loneliness. He was shunned by the villagers because of the Nine - Tails inside him. In many fanfictions, authors explore how he coped with this isolation, like finding solace in small acts of kindness from a few people, such as Iruka - sensei.
In some fanfictions, Naruto and Gaara's childhoods are paralleled. Both were outcasts in a way. Naruto was shunned because of the Nine - Tails inside him, and Gaara was feared for the Shukaku. A fanfiction could explore how they might have found solace in each other's similar experiences, had they known about it earlier.