1 Work in Favorite Malec Stories
In order to save Jace and banish Lilith back to Edom, Magnus decides to summon his father. And Asmodeus is not what Alec first imagined. Alec quite quickly realises that he likes Asmodeus: they are both overprotective of Magnus and think he's beautiful. Plus Alec likes that Asmodeus addresses him as a ''future son in law''.
Or a crackfic in which Asmodeus likes to think that he's a cool dad, but isn't really and keeps embarrassing Magnus.