Greed, Lust, Wrath, Pride, Envy, Gluttony, and Sloth, the seven dragon's sins that Spike has to hold tight inside the back of his mind each day of his life in order to grow up as the best and most reliable dragon this world could have.
Unfortunately for him, his own expertise at keeping those sins at bay make it impossible for his friends to notice his daily struggles. That is until the day Rainbow Dash teased the dragon enough to pop a genius idea into the chaotic mind of Discord.
Note: Thanks to B_25 for his suggestions. I hope to improve my "showing" skills as the times goes on