When he looks back on the time he's spent in the Digital World, Kouichi realizes he's missed out on a lot. At least half of his time was spent as Cherubimon's puppet. Soon after he changed sides, he was dropped from battle in favor of Takuya and Kouji's new Hyper Spirit Evolution—he barely had the chance to get used to his new Spirits before they became obsolete. He didn't get the chance to fight the final battle against Lucemon because he'd been killed; the first time he'd actually fought Lucemon, he'd been taken out of battle, and this time it really could have been permanently. Even looking back into his days as Duskmon, he has to admit (no matter how much he hates to) that Mercuremon was right in saying that he didn't fight much. Back then, he hadn't been interested. It was only when he was starting to get restless and starting to see how utterly pathetic his brethren were that he fought.
But those really were his glory days. Kouichi hates to admit it, but on some level he really misses being Duskmon. He never had to prove to anyone (and especially not to himself) how strong he was. And whenever someone did question him, he could easily defeat anyone. Even Cherubimon appeared to be careful about him, especially when he first became Velgmon.
He doesn't have those luxuries now. Now, he's just an ordinary human still in recovery after a concussion and near-death experience. His chest hurts from hitting the floor in his fall and the doctors' attempts to revive him. He doesn't even want to talk about his head. When the others visit him, they treat him like he's going to break at any second. As time goes on, the immediate injuries fade but there are still scars. The first time he has a migraine, no one knows what to do. They ask him if he wants to sit things out so he doesn't trigger another one. But he doesn't. He doesn't want to have to sit on the sidelines anymore. He doesn't want to have any reason to doubt his own strength or let others doubt him. And some days, he just wants to get mad at them and tell them all this instead of just tolerantly answer, "No, I'll be fine. Don't worry." Some days, he really regrets his Spirits changed because he thinks he changed along with them, and not for the better.
Standard disclaimer applies: I do not own Digimon Frontier. This drabble set is the result of a craving for fics about Kouichi and finding very few (that I hadn't read already) that emphasized his emotional strengths instead of putting him in situations that required another person to get him out of. These are all supposed to take place within the canon universe and are not part of the "Yang-Yin" fanon.