As character names:

U+2751 LOWER RIGHT SHADOWED WHITE SQUARE character (❑)

As raw characters:

❑

As a string of HTML entities:

❑

Decoder output:

Byte number 1 is decimal 226, hex 0xE2, octal \342, binary 11100010
This is the first byte of a 3 byte sequence.

Byte number 2 is decimal 157, hex 0x9D, octal \235, binary 10011101
This is continuation byte 1, expecting 1 more.

Byte number 3 is decimal 145, hex 0x91, octal \221, binary 10010001
This is continuation byte 2, expecting 0 more.

U+2751	LOWER RIGHT SHADOWED WHITE SQUARE