This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
侾 combines 亻 (person) with 孝 (filial piety). The exact historical development and original meaning are uncertain.
A person 亻 beside 孝 (filial piety) suggests a large or imposing figure, but the meaning is unclear.
For コウ, imagine a person 亻 practicing filial piety 孝 with a loud, deep 'koh' sound of respect: koh -> コウ.