The 26-year-old has become the third Ghanaian to sign for the Dragons after Christian Atsu and Daniel Opare and he admits the duo played a role in his decision.
Porto will have to pay around €6 million if they want to make the deal permanent.
“I'm not here for personal glory. I am very happy and ready to give everything I have so that the club can succeed and win trophies,” Waris said, as quoted by Porto Canal.
“It is probably the club in which my dreams can come true, to play in a top league and in the Uefa Champions League. I talked to some friends, Christian Atsu and Opare, who had been here before. They helped me decide to come here,” he added.
The former BK Hacken star believes he will form a good partnership with fellow Africans at the club including Aboubakar, Marega and Brahimi.
“They are fantastic players. They pretty much score all the time. I am also here to help the team score more goals and win. We can probably score a few more goals together. That is the most important thing, not who scores, but that we do it together.
“I think I can match well with them, because they have an offensive mentality, which I also have. It's a matter of understanding each other and working together,” he added.
Waris, who boasts of four goals in 22 appearances for Ghana, joined Lorient in 2015 from Turkish side Trabzonspor, appearing 56 times and scoring 20 goals.