Magnus Bane (in Valentine’s body): You gave me that Omamori charm that I carry with me every day. It was after our night in Tokyo. We were at the Palace Hotel. And we kissed on the terrace. And then you…

Alec Lightwood: Stop!

Magnus Bane: And then you took me in…

Alec Lightwood: How do you know these things?

Magnus Bane: Because… it’s me, Alexander. The day of Valentine’s massacre, you told me that you loved me. So if you love me, please. Please, you have to believe me.

From Shadowhunters – Season 2 Episode 12: ‘You Are Not Your Own’ (2×12)