House Husband? Try Supreme Immortal

Logan Bale is an immortal who has lived for a thousand years, and he takes on a promise made to his dying disciple: to watch over the man's family for three years. To keep that vow, he marries the disciple's granddaughter, but her relatives greet him with contempt and cruelty. He bears their scorn with calm patience, holding to a single private pledge that he will leave once the three years are over.