木偶牵线线拉红绳

The term for 'puppeteer controlling the marionette strings' evokes imagery from traditional puppet shows where characters are animated by tugging strings controlled backstage. In Chinese culture, there's a metaphorical use of a red string connecting people whose fates interwine—hence the inclusion of 'red thread'. The username could signify being bound by destiny while acknowledging outside influences on decisions and direction.