If by BJ then you just need high attraction and don't use the artifact (I think), I had like 80 attraction or something with her. Make sure you pick the highest level of skill checks, i.e Joke lvl 2 over Flirt lvl 1 like the poster above me mentioned.Hi mate !
How can I trigger the scene with Ruby drinking the "baby batter" from MC ?
Cheers !
If you mean the handjob where you finish in her mouth then I think you need to have decent attraction like 60-70 but use the artifact on her.