Somewhere, there is a scene in the middle of a story, where JARVIS thinks about how he hadn't realized Obie was bad/evil/wrong, and now he knows and he won't let it happen again, and he watches everyone around Tony to make sure of it.
ETA: at some time in the fic, JARVIS specifically recalls the Obie-pulling-the-reactor scene in the living room as his reason for being more proactive in his protection.
I really love protective!JARVIS, and would be v.v.thankful if anyone can identify this fanfic.
@mods -
I don't know if character:tony stark tag is appropriate since JARVIS is the focus... help? Thanks for the tag help!
Son of ETA: I can't believe I stumbled upon it accidentally! It was the third story in
icarus_chained's
Tony and Bruce series (AO3 link). I love, love, LOVE this series!