2. An e-hongbao via Wechat.
You can send an e-hongbao (cash-stuffed red envelop) via Wechat with a certain yet special amount of money to your sweetheart, such as 52013.14 yuan (I'll keep loving you for a life time), 33445.20 yuan (I'll love you until the end of the world), 2018.40 yuan (Love you in all my life), 520 yuan (I love you), etc.