Although a "deal" with the Lord of the Star Domain would surely be like making a pact with a tiger, the Lord of the Star Domain would naturally offer Ling Tian some conveniences if he wanted Ling Tian to work for him. For instance, he might give Ling Tian powerful cultivation techniques and secret arts, or even formidable Dan Artifacts. At the very least, he might tell Ling Tian about some of the Lord of the Universe's weaknesses. Any of that would give Ling Tian a better chance of defeating the Lord of the Universe, and that was what mattered most. For Ling Tian, rescuing his friends and family was naturally the most important thing right now. For their sake, he was quite willing to make a deal with the Lord of the Star Domain. As for what came afterward, he could always adjust his plans then.
However, Ling Tian had not received any request from the Lord of the Star Domain, which left him somewhat disappointed. He especially wondered whether it was because his strength was inadequate—or because he simply wasn't worthy of the Lord of the Star Domain's attention—that the latter had never approached him.
So when Ling Tian said those words, he made no attempt to hide his feelings. That quickly convinced the Lord of the Universe. More importantly, the latter knew that now that they had reached an agreement, there was no harm in Ling Tian revealing that he had "colluded" with the Lord of the Universe. Yet Ling Tian hadn't done so, which was enough to show that he wasn't colluding with him.
The Lord of the Universe was undeniably clever. Once he realized Ling Tian had not colluded with the Lord of the Star Domain, he quickly figured out how Ling Tian had learned