Sub-Episodes
Sub-Episodes are side stories in the Sonichu comics, set apart from the main story of Sonichu. They are centred around Chris, and are re-tellings of real-life events that happened to him based within the continuity of the comic books.
Trolls generally prefer the sub-episodes to the regular comics, as Chris's IRL exploits where he is trolled by mall security guards tend to be more amusing than the bland adventures of a Mary Sue Sonic recolor.
Basis & Structure
Typically each sub-episode is inspired by some actual event in Christian's life, notably ones that caused him particular anguish or distress during the earlier years of his Love Quest. Sub-Episodes #1, #4-5, and #7-8 are based on the well-known confrontations Chris had with either the Jerkops or Manajerks in various places around Charlottesville. These particular comics tend to follow a general structure; Chris is confronted by a Manajerk for trying to find true love by loitering in a public area and is told to leave. Chris takes offense to this and transforms into Chris-Chan Sonichu in order to do battle, though ultimately he is defeated, necessitating the arrival of one of his characters to save him. After his foes are vanquished so that they cannot make him leave, Chris delivers a self-important speech with an excessively specific, Chris-centric moral and leaves anyway. Sub-Episode #6 acts as a companion piece of sorts, profiling the various Jerkops and Manajerks out to get Chris (as well as serving up another tiresome self-righteous monologue).
Sub-Episode #2 and #3 are somewhat different; #3 is a fairly boring confrontation between Chris and Mary Lee Walsh based on his numerous grievances with her, but #2 involves absolutely no fight scenes or action at all, and is entirely about Chris being tricked by Hanna into thinking she likes him. This particular incident got Chris banned from the mall for screaming in anguish after finding out she was just screwing with him, though this detail is absent from the comic.
The Sub-Episodes are interesting insights into how Chris sought to resolve his problems during the years they were created. For one, they are a way of seeking external validation -- by presenting these stories as injustices towards his good self, he hopes someone will read them and pity (and therefore love) him. For this reason, the stories always assert Christian's righteousness while dwelling on his pain and suffering; #2 is a particularly good example, presenting the well-meaning and lonely Chris as the subject of a malicious trick in the ultimate portrayal of self-pity. They're also great early examples of Chris's tendency to resort to power fantasies in order to right the perceived wrongs against him, which would become more evident in later issues of Sonichu.
Discontinuation and Legacy
The first four Sub-Episodes appear in Sonichu #0-3, presumably with Chris initially intending on keeping them separate from Sonichu's adventures. However, it's easy to interpret this as Chris using his comic book to attract attention and sympathy to his own plights in a sort of Trojan Horse scheme, which is perhaps true considering that Chris had done something similar not too long beforehand.
Sonichu #4 is notoriously entirely comprised of Sub-Episodes, reprising the first four and introducing four more, with Sonichu himself reduced to cameo appearances. It's not entirely certain whether Chris found only single Sub-Episodes in the previous issues insufficient and was attempting to hammer his point home with an all-Chris issue, or whether he was sort-of fulfilling the wishes of his mother in getting them all out of the way in one fell swoop. In any case, none of the main Sonichu comics after #4 would contain Sub-Episodes.
Whilst the later comics would lack sub-episodes, Chris's tendency to integrate aspects of his life into his comic strips would continue to affect the overall story of Sonichu, with Sonichu #5 straight away involving the marriage of Sarah Hammer and introducing Chris's new-found friend Megan Schroeder. This would come to a head in Sonichu #10, which is best described as a rampant ego trip set against a background of Chris's war with Asperpedia colliding head-on with the already warped continuity of Sonichu.
The Sonichu Special comics are also worth noting, though they involve "real" people in Chris's life within fictionalized events.