<P> During her stay in Alicante, Clary ventures to find Ragnor Fell, who will be able to help her with the potion . She is escorted there by Sebastian Verlac, whom she recently met, in an attempt to make contact with Fell . Instead she finds Magnus Bane . He tells her of Ragnor's death and how he was called as a replacement, and requests that she find him the Book of White in return for his help . She returns to Alicante, where Sebastian kisses her . She rejects him after having feelings of "wrong" while he kissed her, and they continue back to Alicante . She then learns that something called the Book of White has been hidden in Wayland Manor, and travels with Jace to retrieve it . Inside the Manor, they find the angel Ithuriel tied up and left for dead in the basement . He gives both Shadowhunters visions of Valentine experimenting on his children with demon blood in an attempt to make a stronger warrior . </P> <P> They escape from Wayland Manor, after freeing Ithuriel so that he can finally die; the two then share a moment of passionate romance . They return to Alicante to see it burning from the first assault on the city, and after things are in order, Clary meets with the others and they go to free Simon who was taken to a Conclave prison called The Guard . They return to see the Clave, and Clary uses her rune ability to create a binding rune, enabling Shadowhunters and Downworlders to share powers . All those of age go to the battle on Brocelind Plains, and Clary has to give Simon the Mark of Cain so that the vampires will join the fight . </P> <P> At last, Magnus wakes Clary's mother Jocelyn, who informs Clary that Jace is not her brother . In fact, Sebastian (the real Jonathan Morgenstern) is her brother . It is soon revealed that Sebastian is a spy for Valentine and that he tried to seduce Clary into teaming up with him . Clary then tries to locate Jace to help him . She runs into Valentine, who ties her down in order to complete his summoning of the Angel by using her blood . Then, when Jace arrives to rescue her, Valentine forces her to watch as he fatally stabs Jace in the chest . Upon summoning the angel, Clary changes the marks on Valentine's summoning circle, giving her the ability to control the Angel, and after Valentine is slain, she wishes to have Jace back . After Jace is brought back to life, the two get together, now that they know that their love for each other isn't incestuous . </P> <P> In the fourth book, City of Fallen Angels, Clary and Jace are happily in love . But soon, Jace starts to behave strangely and avoids her, leading Clary to assume he wants to break up with her . In truth, he has been influenced by Lilith, who sent him dreams in which he kills or hurts Clary, because when he was raised from the dead by Raziel, all of his protections placed on him at birth were stripped away, leaving him vulnerable to demonic influence . During the party, when Lucian's pack celebrated his engagement with Clary's mother Jocelyn, she is kidnapped by a fully possessed Jace and taken to Lilith . There, she learns her brother Jonathan Christopher Morgenstern / Sebastian Verlac is going to be raised from the dead by Simon, and she was brought just to make him do that . Using Jace's affection for her (which remains undiminished because his possession has no effect on that part of him), she cuts the rune which enabled Lilith to control him . Seeing his chance, Simon destroys Lilith with his Mark of Cain . After Lilith's destruction, Isabelle and Alec appear on the scene, but Jace shoos them away since he doesn't want to be consoled as he feels terrible for hurting Clary, in spite of the fact that he wasn't himself . Alec then shoves Clary back to the room as they get into the elevator, feeling that only she can help him . Clary and Jace reaffirm their love after she convinces him he is not a horrible person . The last words Clary says to him before going down are, "I'll be back . Five minutes," and they share a kiss before she leaves and comes back to find him gone, unaware his rune has healed and he is possessed once again . </P>

In the mortal instruments are clary and jace related