Circle Eyes

In manga and anime, "circle eyes," maru-me ○目, are eyes drawn as white circles with black outlines, typically used when a character is overwhelmed, shocked, startled, or scared, but sometimes just a simple way to draw eyes when they're being silly.^{(tonbi.jp:〇目)}

Effectively, they're a simplified type of "white eyes," shirome 白目.

It's also spelled maru-me 丸目, and also called zero-me ○目, because they look like zeroes.

Akaza Akari 赤座あかり, example of hair strands sticking out of an overwhelmed character.

Anime: Yuru Yuri ゆるゆり (Episode 1)

Hair strands sticking out also symbolize being overwhelmed.

Examples

Anime: Watashi, Nouryoku wa Heikinchi de tte Itta yo ne! 私、能力は平均値でって言ったよね！ (Episode 6)

See realization mark for the ∑-shaped icons.

Asagaya Minoa 阿佐ヶ谷未乃愛, example of "circle eyes," maru-me ○目.

Character: Asagaya Minoa 阿佐ヶ谷未乃愛
Anime: Animegataris, アニメガタリズ (Episode 1)

Ichii Tooru 一井透 and Momoki Run 百木るん holding hands using overly long sleeves (moe-sode 萌え袖) as protection.

Left: Ichii Tooru 一井透
Right: Momoki Run 百木るん
Anime: A-Channel, Ａチャンネル (Episode 4)

Context: Tooru practices protected hand-holding by wearing overly long sleeves.

Dino ディーノ, soul coming out of his mouth.

Character: Dino, ディーノ
Anime: Blend S, ブレンド・S (Episode 5)

Context: Dino's soul comes out of his mouth after receiving a huge shock.

Manga: K-On!, Keion! けいおん！ (Volume 1, Page 30)

Context: Hirasawa Yui 平沢唯, who started learning to play the guitar, tells her impressions about the guitar strings to Tainaka Ritsu 田井中律.
{hosokute katai kara} yubi φ kichaisou
細くて硬いから指切っちゃいそう
{Because [they] are thin and hard}, [it feels like] [it] will cut [my] fingers.
- Symbol: plewds, a type of sweat drop drawn on air.
- kichaisou - contraction of kitte-shimai-sou.
piin
ピーン
*sound effect of the idea light bulb turning on*