The writers won't be doing their job if they didn't make you people try to figure out who Alto is going to go after.
Note about the Zentradi names:
The spellings are intentional since they denote that they're not human. Were the the Zentradi human, we would use the Romanization of their names (which is also perfectly acceptable).
The fact that the womanizer had to tell Ranka that Alto wasn't coming shows Alto's selfish side. The least he could have done was call her, maybe leave a message. But I'll let it slide this time since it's his birthday present and that his family decided to give him a hard time, again. But as I've said, the ball is in Sheryl's court. It will go back to Ranka's as part of the natural order of things. Then back to Sheryl, then back to Ranka, wash, rinse, repeat, etc.