Goodness. Zichen allows the tantrum for a minute before he grabs Xue Yang and purposefully traps him in an embrace. It will never be pleasant - not how they are now (and with Zichen's breath containing that tell-tale rattle of death) - but this keeps the gremlin still. He isn't even judging Xue Yang for crying! He has done it enough for a few weeks now to know it can be a release.