This would go hard with ARG fans

>>you lost me at "emoji" （ ´,_ゝ`）
>>fine. onomotopoeias and interjections then...
They used a kaomoji, so I doubt they're saying "no interpretive images"
:) - emoticon (simplistic faces and symbols made from text)
( ´ ▽ ` )ﾉ - kaomoji (really just the japanese version of emoticons, but they tend to use symbols noy easily found on western keyboards)
🙂 - emoji (idk about Kimura-sensei, but a lot of people stopped liking these because certain websites automatically convert :) into 🙂 which already has a different vibe from :) but also has a different vibe depending on what OS you're looking through)

Personally I'm kind of a fan of the deviantART and old Android emojis, as far as emojis go