As character names:

U+30FC KATAKANA-HIRAGANA PROLONGED SOUND MARK character (ー)

As raw characters:

ー

As a string of HTML entities:

ー

Decoder output:

Byte number 1 is decimal 227, hex 0xE3, octal \343, binary 11100011
This is the first byte of a 3 byte sequence.

Byte number 2 is decimal 131, hex 0x83, octal \203, binary 10000011
This is continuation byte 1, expecting 1 more.

Byte number 3 is decimal 188, hex 0xBC, octal \274, binary 10111100
This is continuation byte 2, expecting 0 more.

U+30FC	KATAKANA-HIRAGANA PROLONGED SOUND MARK
	x (em dash - 2014)