Nagumo's most notable traits are his laid-back attitude and his constant smile, which seems impossible to wipe off his face. He also has an incredible talent for annoying those around him to the point where they wish him dead.[༡༢][༡༣][༡༤] He has a habit of teasing others with his slightly dark jokes.[༡༥] However, deep down he is a kind and caring person.[༡༦][༡༧] He tends to speak excitedly and in a sing-song manner,

Nagumo has many tattoos, most of which are hidden by his clothing. His tattoos have symbolic, philosophical, and mathematical inspirations, particularly referencing the golden ratio.

The tattoos shown include:

On the left side of his neck, he has a Fibonacci Spiral mark.
The growth factor of the Fibonacci spiral is the golden ratio, ~1.6180.
Two rectangular tattoos on both hands, another reference to the golden ratio.
The formula
φ

1
+
1
+
1
+
1
+
1
+
1
+
1
+
⋯
{\displaystyle \phi ={\sqrt {1+{\sqrt {1+{\sqrt {1+{\sqrt {1+{\sqrt {1+{\sqrt {1+{\sqrt {1+\cdots }}}}}}}}}}}}}}}}}On his right forearm.
This is a presentation of an infinite sequence of nested square roots that resolves to ~1.6180... (the golden ratio).
5 rectangles with different designs (and the third and fifth of which are black), next to the formula tattoo.
The symbols, '2', '
φ
{\displaystyle \phi }', '1' and '%' on his index, middle, ring and pinky fingers respectively.
A snake coiled around the lower part of her left leg.
A swallow on the right side of her right leg, just below the knee.
An impossible shape on his shin, beneath the swallow tattoo.
A square made of several lines and curves spaced apart on her right thigh.
A mandala-style pattern on her right shoulder.
A pair of hands praying on his left pectoral.
Probably inspired by Albrecht Dürer's drawing of Praying Hands.
Quote from Anton Chekhov "Even if you can tell lies, people will believe you, if only you speak with authority" on his right bicep[༩]
A line that crosses, wrapping around his front forearm.
An isosceles triangle pattern on his left posterior forearm.
A rectangular tattoo on his right tricep.
A tattoo that is a reference to Leonard Shelby from Christopher Nolan's Memento, on his left bicep.[༩]
A wing on her left waist

Nagumo is a handsome man of tall, slender but muscular build, with medium-length black hair and large black eyes.

Their outfits usually consist of a black tank top, navy blue shorts or floor-length trousers, and a pair of wooden sandals or sneakers.

BIOGRAPHICAL INFORMATION
JAPANESE NAME
南ナ雲グモ与ヨ市イチ
ALIAS
Nacchan (なっちゃん?)[༡]
PERSONAL DESCRIPTION
BIRTHDAY
July 9[༢]
AGE
27[༣][༢]
GENDER
Man
HEIGHT
190 centimeters[༢]
WEIGHT
78 kilos[༢]
EYE COLOR
Brown (anime)
Black (sleeve)

HAIR COLOR
Black