Even this new girl can see that Seishirou likes Raku. Also, if they actually did steal a kiss, it would be the first on-the-lips kiss for him. Every other kiss he's had so far was on some other part of his body. (but I know for a fact it never comes to that- Paula is forced to surrender before Seishirou has to steal his first kiss away from Chitoge)
This and the next chapter that continues this challenge are part of the second episode of the second season, and it was a real fun watch animated. I wonder if the manga can convey the same hectic action of the fight. The slower parts for sure can be conveyed well, but animation feels better to me for fights.
Fortunately, the climax of the battle is probably one of the slowest parts, so still panels should convey it well. It's mostly intimidating aura.