Hahaha I imagine Taeui would be very happy to go! He might even try to encourage Ilay to go with him.
Ilay would probably think he’s seeing the therapist to leave him (he’s not wrong) and would stop him from going/ threaten the therapist. Taeui would exasperatedly give up to save the therapist (but would secretly follow online sessions from a different country instead).
ORRRRR The therapist would catch a glimpse of Ilay’s psychiatric history and would run in the other direction and poor Taeui would wonder why no one is willing to work with him hahah

love how this is just a textbook case of stockholm syndrome. taeui, please go to therapy