"Almost Heart-Warming" should start with the appearance of being Heart-Warming before subverting that expectation at the end. Akebono is not being malicious at the start; she's just being harsh while making a good point, and the end shows that she likes the admiral a lot more than she lets on. Thus, it's both "Heart-Warming" and "Mixed Signals".
Look at this flabby stomach! You say you don't want to exercise because it's cold!?Ahhh, I see!Did the Admiral do something that made her angry?Ah, jeez, stop lazing around in your room just because it's cold outside, you shitty Admiral!Get a hold of yourself and work!!So let's exercise outside!!Akebono-chan seems a bit too prickly today, doesn't she?Nope, that's not iiiit!Th-then..I'll warm your hands up...Get hold of yourself, okay!