Ace's self doubt and sadness are vanished when his best (girl) friend cheers him up.
Apparently a comic follow-up of this artwork Another Ace x Pinkie interaction, but it isn't direct shipping here, but more a friendshipping. Plus, it shows how he's quite bigger than her. Yes, the monologue (or something like that) is coming from Pinkie's trademark "Smile Song" — I think it fits this situation well.
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