There are a lot of Characterization Tropes that can be used to quickly and non-verbally introduce a character, and one of the sadder ones is the Friendless Background. The character will, through fate or choice, be presented as not having any friends, or at least not within easy visiting or communication range. They will be eating lunch alone, or looking forlornly/enviously at others with friends and Love Interests, and usually be found immersed in reading, video games, or some other highly solitary activity.
These are the most common causes:
Newcomer: Be they a New Transfer Student in a new school, an employee at a new work place, or having escaped their Doomed Hometown as a refugee.
The Loner: Might be because of preference or ostracism. Freakishness optional. Jerkass-ness optional.
Homeschooled: Similar to Newcomer, the character has grown up or lived away from others. May or may not come with interesting psychological quirks.
Trauma: Some sadness like parental abuse (often seen in Dark Magical Girls) or other kind of angst may keep the character from letting anyone close to them, can result in The Woobie.
Shyness: Some characters (like in real life) are insecure of themselves for whatever reason and are not even able to talk to other people (sometimes temporary).
Lack of self-confidence: Similar to the one above, the character may believe they're not worthy of other people's friendship while craving acceptance. Or possibly they want to feel like they're important, but don't. Many Shrinking Violet characters are prone to this.
Incompetence: A character may simply lack the social intuition required to connect with others, regardless of how willing or confident they are.
Unattractiveness: The character is physically repulsive and avoided or mistreated because of that.
The last five types can result in envy for more extroverted characters (like Misao from Magical Project S).
What's curious about this Dark and Troubled Past (or present) is that it's incredibly easy to fix. "When you have nothing to lose, you stand to gain everything", so to speak. In short order the character will Crash into Hello, get in a fight, drop their groceries or make a new friend through less quirky means. Before long they'll make loads more friendsnote or join a group of them. Despite their lack of social skills or experience they'll magnetically gather new friends thanks to their at times strange but honest charm and learn to use The Power of Friendship to its fullest.
Of course you can expect the "genuine" loners who become one of the True Companions to moan about being stuck With Friends Like These... — all while secretly thanking them all.
In more tragic cases, a friendless character whose new friends turn out to be False Friends is very vulnerable to falling to despair or even worse things.
It should be mentioned that this can become implied against the author's wishes if the character never mentions or demonstrates having had friends before meeting their new ones, and/or never hangs out with anyone outside their Limited Social Circle. Fridge Loners, so to speak. If they had any friends, they're kind of like a set of living Forgotten Fallen Friends. Of course, this can be fixed by introducing a Beleaguered Childhood Friend, showing a photo album, or introducing Those Two Guys as friends.
Related to I Just Want to Have Friends and compare with Social Circle Filler when an author wants to prevent this initially. Compare Alone in a Crowd and Only Friend.
