Ritual disembowelment. You are wearing a method of suicide.

What a Japanese person actually thinks
Alarming rather than noble. Japanese readers do not experience this word as romantic — it names a physical act, and the characters describe it plainly. Many people will read it as a statement about self-harm.

Meaning

Literally: cut + belly
Actually: The samurai ritual of suicide by cutting open the abdomen. Extremely specific, extremely literal.

Scores

Naturalness●●●●●

Correct word for the practice.

Coolness●●●●●

The characters are blunt: 'cut' and 'belly'. There's no poetry in the compound at all.

Watch out

highThis may reasonably be read as referencing suicide. Consider how it will land with people who care about you, and with strangers.
highJapan has a serious ongoing conversation about suicide. This word is not treated as a historical curiosity.

Get this instead

武士道 bushidō
the warrior's code

If the appeal was the samurai ethic of accepting consequences, the code itself is the thing to wear — not one grim clause of it.
覚悟 kakugo
resolve; having accepted the consequences

The mindset without the act. This is genuinely the concept you're reaching for.

On skin

切腹

Orientation: either

N/A — please choose something else.