If Reisen can't see you normally,

how about using a special situation to contact her instead?

Like visiting her when she's asleep...

You dummy! How could she see me when she's unconsious!

She can't even see me when she's awake,

there's no way she can see me when asleep. That would be in a dream!

In a dream...

AH~~!!

You never thought of this before, did you...