Identifying the subject of spells and spell like abilitys

[Cpt Isaac]

I have a player arguing that since their spell like ability has no components that he can cast it in public and no one can tell that he casted it as their is no visible effect.
The spell specifically is charm.
So my question is. Is their a visible effect to spells like charm and others? Or do they just happen without anyone being able to tell other than the creature freezes up for a moment (Not even as they can still walk with their move action)

[blahpers]

The Dreaded Spell Manifestion FAQ

Basically, even a spell-like ability (or a still silent spell with no materials) makes glowing balls or whooshy sparkly runes or whatever that anybody with eyes can see. This keeps secret spellcasting very, very hard to pull off, because Paizo hates that.