Eehh...so Souta becomes an angsty teenager? well, although it's somewhat realistic (seen plenty teens acting like this), it's just bland when compared to Hori and Miyamura, meh
Why is Sota being such an ass? His words are super harsh bordering on cruel, in both chapters, and then he does something 'sweet' or ends with a compliment.
No wonder that girl is having whiplash.
Her behaviour is a normal annoying but he's just weirdly hot n cold.