Sword Gai The Animation

both shows use 'special humans' to fight within an organization, giant robots, lots of fun psychedelic brain twisting talk. lots and lots of killing and blood :D 

both shows have people who transform into cgi demons, fight with swords.. masses of people die, elements of bullying/discrimination/suicide plot revolves a 'saving humanity /humanity has fallen' lots of death.. 

Both anime have a demon theme character with a sword that hunt demons. Both of these anime are filled with action, blood, gore and cool characters. If you like one, you should enjoy the other. 

Both have demon swords. Though, Inuyasha is more focused on the Sengoku Era of Japan where youkai/demons roam. And the swords actually make sense in being good or evil and how they became that way. 

Both anime take place in a sci-fi/fantasy urban setting and follow characters who hunt those who are possessed. Each anime occasionally break off from the main characters to follow the possessed and tell their stories. Each has CGI Sword Fights, lots of driving sequences, and are quite gory. 

In both you have no idea what the hell is going on throughout the episodes, and as they try to cover up plot holes and clear up confusion it gets even more confusing. Both are pretty dark animes with darker colors. ALso deaths.... many many deaths... Setting and characters are different tho 

Disappointed? Try a better story about another "Sword Guy" Also, each show has a unique animation style.